CRC DEPLETION CALCULATIONS FOR THE NON-RODDED ASSEMBLIES IN BATCHES 4 AND 5 OF CRYSTAL RIVER UNIT 3

International Nuclear Information System (INIS)

Wright, Kenneth D.

1997-01-01

The purpose of this design analysis is to document the SAS2H depletion calculations of certain non-rodded fuel assemblies from batches 4 and 5 of the Crystal River Unit 3 pressurized water reactor (PWR) that are required for commercial Reactor Critical (CRC) evaluations to support the development of the disposal criticality methodology. A non-rodded assembly is one which never contains a control rod assembly (CRA) or an axial power shaping rod assembly (APSRA) during its irradiation history. The objective of this analysis is to provide SAS2H generated isotopic compositions for each fuel assembly's depleted fuel and depleted burnable poison materials. These SAS2H generated isotopic compositions are acceptable for use in CRC benchmark reactivity calculations containing the various fuel assemblies

CRC DEPLETION CALCULATIONS FOR THE NON-RODDED ASSEMBLIES IN BATCHES 4 AND 5 OF CRYSTAL RIVER UNIT 3

Energy Technology Data Exchange (ETDEWEB)

Kenneth D. Wright

1997-07-30

The purpose of this design analysis is to document the SAS2H depletion calculations of certain non-rodded fuel assemblies from batches 4 and 5 of the Crystal River Unit 3 pressurized water reactor (PWR) that are required for commercial Reactor Critical (CRC) evaluations to support the development of the disposal criticality methodology. A non-rodded assembly is one which never contains a control rod assembly (CRA) or an axial power shaping rod assembly (APSRA) during its irradiation history. The objective of this analysis is to provide SAS2H generated isotopic compositions for each fuel assembly's depleted fuel and depleted burnable poison materials. These SAS2H generated isotopic compositions are acceptable for use in CRC benchmark reactivity calculations containing the various fuel assemblies.

CRC DEPLETION CALCULATIONS FOR THE NON-RODDED ASSEMBLIES IN BATCHES 1, 2, AND 3 OF CRYSTAL RIVER UNIT 3

International Nuclear Information System (INIS)

Wright, Kenneth D.

1997-01-01

The purpose of this design analysis is to document the SAS2H depletion calculations of certain non-rodded fuel assemblies from batches 1, 2, and 3 of the Crystal River Unit 3 pressurized water reactor (PWR) that are required for Commercial Reactor Critical (CRC) evaluations to support development of the disposal criticality methodology. A non-rodded assembly is one which never contains a control rod assembly (CRA) or an axial power shaping rod assembly (APSRA) during its irradiation history. The objective of this analysis is to provide SAS2H generated isotopic compositions for each fuel assembly's depleted fuel and depleted burnable poison materials. These SAS2H generated isotopic compositions are acceptable for use in CRC benchmark reactivity calculations containing the various fuel assemblies

A versatile passive and active non-destructive device for spent fuel assemblies monitoring

International Nuclear Information System (INIS)

Berne, R.; Bignan, G.; Andrieu, G.; Dethan, B.

1993-01-01

The monitoring of spent fuel assemblies in reactor pools or in reprocessing plants with NDA methods is interesting (non-destructivity, non-intrusivity) for process control, safety-criticality and/or nuclear material management. In this context, the authors present the results of the development and design of a prototype device (physical methods used, qualification...) called PYTHON. The aim of PYTHON is to check the declared characteristic values of an irradiated assembly before taking it into a transport cask for safety criticality control. The PYTHON device consists of a detector head in two sections and a 252 Cf source if active neutron counting is to be used. Each section of the detection head consists of two detectors: one fission chamber and one ionization chamber

The non-covalent decoration of self-assembling protein fibers.

Science.gov (United States)

Mahmoud, Zahra N; Grundy, Daniel J; Channon, Kevin J; Woolfson, Derek N

2010-10-01

The design of self-assembling fibers presents challenges in basic science, and has potential for developing materials for applications in areas such as tissue engineering. A contemporary issue in the field is the construction of multi-component, functionalized systems. Previously, we have developed peptide-based fibers, the SAF system, that comprises two complementary peptides, which affords considerable control over assembly and morphology. Here we present a straightforward route to functionalizing the SAFs with small molecules and, subsequently, other moieties. This is achieved via non-covalent recruitment of charged peptide tags, which offers advantages such as further control, reversibility, and future prospects for developing recombinant tags. We demonstrate the concept by appending fluorescent labels and biotin (and thence gold nanoparticles) to the peptides, and visualising the resulting decorated SAFs by light and electron microscopy. The peptide tags bind in the nm-mum range, and show specificity compared with control peptides, and for the SAFs over similar alpha-helix-based peptide fibers. 2010 Elsevier Ltd. All rights reserved.

Self-assembled materials and supramolecular chemistry within microfluidic environments: from common thermodynamic states to non-equilibrium structures.

Science.gov (United States)

Sevim, S; Sorrenti, A; Franco, C; Furukawa, S; Pané, S; deMello, A J; Puigmartí-Luis, J

2018-05-01

Self-assembly is a crucial component in the bottom-up fabrication of hierarchical supramolecular structures and advanced functional materials. Control has traditionally relied on the use of encoded building blocks bearing suitable moieties for recognition and interaction, with targeting of the thermodynamic equilibrium state. On the other hand, nature leverages the control of reaction-diffusion processes to create hierarchically organized materials with surprisingly complex biological functions. Indeed, under non-equilibrium conditions (kinetic control), the spatio-temporal command of chemical gradients and reactant mixing during self-assembly (the creation of non-uniform chemical environments for example) can strongly affect the outcome of the self-assembly process. This directly enables a precise control over material properties and functions. In this tutorial review, we show how the unique physical conditions offered by microfluidic technologies can be advantageously used to control the self-assembly of materials and of supramolecular aggregates in solution, making possible the isolation of intermediate states and unprecedented non-equilibrium structures, as well as the emergence of novel functions. Selected examples from the literature will be used to confirm that microfluidic devices are an invaluable toolbox technology for unveiling, understanding and steering self-assembly pathways to desired structures, properties and functions, as well as advanced processing tools for device fabrication and integration.

Self-assembly and transformation of hybrid nano-objects and nanostructures under equilibrium and non-equilibrium conditions

Science.gov (United States)

Mann, Stephen

2009-10-01

Understanding how chemically derived processes control the construction and organization of matter across extended and multiple length scales is of growing interest in many areas of materials research. Here we review present equilibrium and non-equilibrium self-assembly approaches to the synthetic construction of discrete hybrid (inorganic-organic) nano-objects and higher-level nanostructured networks. We examine a range of synthetic modalities under equilibrium conditions that give rise to integrative self-assembly (supramolecular wrapping, nanoscale incarceration and nanostructure templating) or higher-order self-assembly (programmed/directed aggregation). We contrast these strategies with processes of transformative self-assembly that use self-organizing media, reaction-diffusion systems and coupled mesophases to produce higher-level hybrid structures under non-equilibrium conditions. Key elements of the constructional codes associated with these processes are identified with regard to existing theoretical knowledge, and presented as a heuristic guideline for the rational design of hybrid nano-objects and nanomaterials.

The approximate thermal-model-testing method for non-stationary temperature fields in central zones of fast reactor assemblies

International Nuclear Information System (INIS)

Mikhin, V.I.; Matukhin, N.M.

2000-01-01

The approach to generalization of the non-stationary heat exchange data for the central zones of the nuclear reactor fuel assemblies and the approximate thermal-model-testing criteria are proposed. The fuel assemblies of fast and water-cooled reactors with different fuel compositions have been investigated. The reason of the non-stationary heat exchange is the fuel-energy-release time dependence. (author)

Destruction of plutonium using non-uranium fuels in pressurized water reactor peripheral assemblies

International Nuclear Information System (INIS)

Chodak, P. III

1996-05-01

This thesis examines and confirms the feasibility of using non-uranium fuel in a pressurized water reactor (PWR) radial blanket to eliminate plutonium of both weapons and civilian origin. In the equilibrium cycle, the periphery of the PWR is loaded with alternating fresh and once burned non-uranium fuel assemblies, with the interior of the core comprised of conventional three batch UO 2 assemblies. Plutonium throughput is such that there is no net plutonium production: production in the interior is offset by destruction in the periphery. Using this approach a 50 MT WGPu inventory could be eliminated in approximately 400 reactor years of operation. Assuming all other existing constraints were removed, the 72 operating US PWRs could disposition 50 MT of WGPu in 5.6 years. Use of a low fissile loading plutonium-erbium inert-oxide-matrix composition in the peripheral assemblies essentially destroys 100% of the 239 Pu and ≥90% total Pu over two 18 month fuel cycles. Core radial power peaking, reactivity vs EFPD profiles and core average reactivity coefficients were found to be comparable to standard PWR values. Hence, minimal impact on reload licensing is anticipated. Examination of potential candidate fuel matrices based on the existing experience base and thermo-physical properties resulted in the recommendation of three inert fuel matrix compositions for further study: zirconia, alumina and TRISO particle fuels. Objective metrics for quantifying the inherent proliferation resistance of plutonium host waste and fuel forms are proposed and were applied to compare the proposed spent WGPu non-uranium fuel to spent WGPu MOX fuels and WGPu borosilicate glass logs. The elimination disposition option spent non-uranium fuel product was found to present significantly greater barriers to proliferation than other plutonium disposal products

Destruction of plutonium using non-uranium fuels in pressurized water reactor peripheral assemblies

Energy Technology Data Exchange (ETDEWEB)

Chodak, III, Paul [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

1996-05-01

This thesis examines and confirms the feasibility of using non-uranium fuel in a pressurized water reactor (PWR) radial blanket to eliminate plutonium of both weapons and civilian origin. In the equilibrium cycle, the periphery of the PWR is loaded with alternating fresh and once burned non-uranium fuel assemblies, with the interior of the core comprised of conventional three batch UO₂ assemblies. Plutonium throughput is such that there is no net plutonium production: production in the interior is offset by destruction in the periphery. Using this approach a 50 MT WGPu inventory could be eliminated in approximately 400 reactor years of operation. Assuming all other existing constraints were removed, the 72 operating US PWRs could disposition 50 MT of WGPu in 5.6 years. Use of a low fissile loading plutonium-erbium inert-oxide-matrix composition in the peripheral assemblies essentially destroys 100% of the ²³⁹Pu and ≥90% {sub total}Pu over two 18 month fuel cycles. Core radial power peaking, reactivity vs EFPD profiles and core average reactivity coefficients were found to be comparable to standard PWR values. Hence, minimal impact on reload licensing is anticipated. Examination of potential candidate fuel matrices based on the existing experience base and thermo-physical properties resulted in the recommendation of three inert fuel matrix compositions for further study: zirconia, alumina and TRISO particle fuels. Objective metrics for quantifying the inherent proliferation resistance of plutonium host waste and fuel forms are proposed and were applied to compare the proposed spent WGPu non-uranium fuel to spent WGPu MOX fuels and WGPu borosilicate glass logs. The elimination disposition option spent non-uranium fuel product was found to present significantly greater barriers to proliferation than other plutonium disposal products.

Comparative Genomics Analyses Reveal Extensive Chromosome Colinearity and Novel Quantitative Trait Loci in Eucalyptus

Science.gov (United States)

Weng, Qijie; Li, Mei; Yu, Xiaoli; Guo, Yong; Wang, Yu; Zhang, Xiaohong; Gan, Siming

2015-01-01

Dense genetic maps, along with quantitative trait loci (QTLs) detected on such maps, are powerful tools for genomics and molecular breeding studies. In the important woody genus Eucalyptus, the recent release of E. grandis genome sequence allows for sequence-based genomic comparison and searching for positional candidate genes within QTL regions. Here, dense genetic maps were constructed for E. urophylla and E. tereticornis using genomic simple sequence repeats (SSR), expressed sequence tag (EST) derived SSR, EST-derived cleaved amplified polymorphic sequence (EST-CAPS), and diversity arrays technology (DArT) markers. The E. urophylla and E. tereticornis maps comprised 700 and 585 markers across 11 linkage groups, totaling at 1,208.2 and 1,241.4 cM in length, respectively. Extensive synteny and colinearity were observed as compared to three earlier DArT-based eucalypt maps (two maps with E. grandis × E. urophylla and one map of E. globulus) and with the E. grandis genome sequence. Fifty-three QTLs for growth (10–56 months of age) and wood density (56 months) were identified in 22 discrete regions on both maps, in which only one colocalizaiton was found between growth and wood density. Novel QTLs were revealed as compared with those previously detected on DArT-based maps for similar ages in Eucalyptus. Eleven to 585 positional candidate genes were obained for a 56-month-old QTL through aligning QTL confidence interval with the E. grandis genome. These results will assist in comparative genomics studies, targeted gene characterization, and marker-assisted selection in Eucalyptus and the related taxa. PMID:26695430

Comparative Genomics Analyses Reveal Extensive Chromosome Colinearity and Novel Quantitative Trait Loci in Eucalyptus.

Directory of Open Access Journals (Sweden)

Fagen Li

Full Text Available Dense genetic maps, along with quantitative trait loci (QTLs detected on such maps, are powerful tools for genomics and molecular breeding studies. In the important woody genus Eucalyptus, the recent release of E. grandis genome sequence allows for sequence-based genomic comparison and searching for positional candidate genes within QTL regions. Here, dense genetic maps were constructed for E. urophylla and E. tereticornis using genomic simple sequence repeats (SSR, expressed sequence tag (EST derived SSR, EST-derived cleaved amplified polymorphic sequence (EST-CAPS, and diversity arrays technology (DArT markers. The E. urophylla and E. tereticornis maps comprised 700 and 585 markers across 11 linkage groups, totaling at 1,208.2 and 1,241.4 cM in length, respectively. Extensive synteny and colinearity were observed as compared to three earlier DArT-based eucalypt maps (two maps with E. grandis × E. urophylla and one map of E. globulus and with the E. grandis genome sequence. Fifty-three QTLs for growth (10-56 months of age and wood density (56 months were identified in 22 discrete regions on both maps, in which only one colocalizaiton was found between growth and wood density. Novel QTLs were revealed as compared with those previously detected on DArT-based maps for similar ages in Eucalyptus. Eleven to 585 positional candidate genes were obained for a 56-month-old QTL through aligning QTL confidence interval with the E. grandis genome. These results will assist in comparative genomics studies, targeted gene characterization, and marker-assisted selection in Eucalyptus and the related taxa.

Physical characteristics of non-fuel assembly reactor components

International Nuclear Information System (INIS)

Hawkes, E.C.

1994-09-01

The primary objective of this report is to enhance the utility of the Characteristics Data Base (CDB). This has been accomplished by providing a pictorial representation of the principal non-fuel assembly (NFA) components along with a tabular summary of key information about each type of component. This report is intended for use as an adjunct to the CDB. Toward this end, the report may be used either as a complement to the detailed descriptions in the CDB, or as a stand-alone document that acts as an illustrated abstract of the CDB. Line drawings of major NFA components are included. Data not provided in the CDB are also included. Summary descriptions of each component are given in tabular format

Non-fuel assembly components: 10 CFR 61.55 classification for waste disposal

International Nuclear Information System (INIS)

Migliore, R.J.; Reid, B.D.; Fadeff, S.K.; Pauley, K.A.; Jenquin, U.P.

1994-09-01

This document reports the results of laboratory radionuclide measurements on a representative group of non-fuel assembly (NFA) components for the purposes of waste classification. This document also provides a methodology to estimate the radionuclide inventory of NFA components, including those located outside the fueled region of a nuclear reactor. These radionuclide estimates can then be used to determine the waste classification of NFA components for which there are no physical measurements. Previously, few radionuclide inventory measurements had been performed on NFA components. For this project, recommended scaling factors were selected for the ORIGEN2 computer code that result in conservative estimates of radionuclide concentrations in NFA components. These scaling factors were based upon experimental data obtained from the following NFA components: (1) a pressurized water reactor (PWR) burnable poison rod assembly, (2) a PVM rod cluster control assembly, and (3) a boiling water reactor cruciform control rod blade. As a whole, these components were found to be within Class C limits. Laboratory radionuclide measurements for these components are provided in detail

Optimization of de novo transcriptome assembly from high-throughput short read sequencing data improves functional annotation for non-model organisms

Directory of Open Access Journals (Sweden)

Haznedaroglu Berat Z

2012-07-01

Full Text Available Abstract Background The k-mer hash length is a key factor affecting the output of de novo transcriptome assembly packages using de Bruijn graph algorithms. Assemblies constructed with varying single k-mer choices might result in the loss of unique contiguous sequences (contigs and relevant biological information. A common solution to this problem is the clustering of single k-mer assemblies. Even though annotation is one of the primary goals of a transcriptome assembly, the success of assembly strategies does not consider the impact of k-mer selection on the annotation output. This study provides an in-depth k-mer selection analysis that is focused on the degree of functional annotation achieved for a non-model organism where no reference genome information is available. Individual k-mers and clustered assemblies (CA were considered using three representative software packages. Pair-wise comparison analyses (between individual k-mers and CAs were produced to reveal missing Kyoto Encyclopedia of Genes and Genomes (KEGG ortholog identifiers (KOIs, and to determine a strategy that maximizes the recovery of biological information in a de novo transcriptome assembly. Results Analyses of single k-mer assemblies resulted in the generation of various quantities of contigs and functional annotations within the selection window of k-mers (k-19 to k-63. For each k-mer in this window, generated assemblies contained certain unique contigs and KOIs that were not present in the other k-mer assemblies. Producing a non-redundant CA of k-mers 19 to 63 resulted in a more complete functional annotation than any single k-mer assembly. However, a fraction of unique annotations remained (~0.19 to 0.27% of total KOIs in the assemblies of individual k-mers (k-19 to k-63 that were not present in the non-redundant CA. A workflow to recover these unique annotations is presented. Conclusions This study demonstrated that different k-mer choices result in various quantities

Non linear characterisation of optical components of a high power laser chain

International Nuclear Information System (INIS)

Santran, Stephane

2000-01-01

This work concerns the realisation of non linear properties measurement prototypes in glasses in the near infrared and in the visible range. The various devices are time resolved colinear pump probe experiments in which the non linear susceptibility is deduced by the probe beam intensity variations induced by the pump probe coupled in the material. The sensitivity of these experiments allows us to observe unexpected variations, greater than 30%, of several fused silica non linear indexes. As well, this allow us to analyse the origin of the promising oxide glasses non linearity for all optical applications and to understand an d measure non linear processes in the two photons photodiodes. Finally, an original structure for the non linear index measurement in non degenerated configuration by a probe pulse phase measurement approach with a Sagnac interferometer is demonstrated and analysed. (author) [fr

Non-ideal assembly of the driving unit affecting shape of load-displacement curves

International Nuclear Information System (INIS)

Huang, Hu; Zhao, Hongwei

2015-01-01

The results of nanoindentation testing strongly rely on load-displacement curves, but an abnormal load-displacement curve with obvious inflection in the unloading portion was commonly observed in previously published papers and the reason is not clear. In this paper, possible reasons involved in a custom-made indentation instrument, such as sensors, control and assembly issues, are analyzed and discussed step by step. Experimental results indicate that non-ideal assembly of the precision driving unit strongly affects the shape of the load-displacement curve and its affecting mechanism is studied by theoretical analysis and finite element simulations. This paper reveals the reason leading to the abnormal load-displacement curve, which is helpful for debugging of indentation instruments and can enhance comparability of indentation results. (paper)

Non-equilibrium magnetic colloidal dispersions at liquid-air interfaces: dynamic patterns, magnetic order and self-assembled swimmers

International Nuclear Information System (INIS)

Snezhko, Alexey

2011-01-01

Colloidal dispersions of interacting particles subjected to an external periodic forcing often develop nontrivial self-assembled patterns and complex collective behavior. A fundamental issue is how collective ordering in such non-equilibrium systems arises from the dynamics of discrete interacting components. In addition, from a practical viewpoint, by working in regimes far from equilibrium new self-organized structures which are generally not available through equilibrium thermodynamics can be created. In this review spontaneous self-assembly phenomena in magnetic colloidal dispersions suspended at liquid-air interfaces and driven out of equilibrium by an alternating magnetic field are presented. Experiments reveal a new type of nontrivially ordered self-assembled structures emerging in such systems in a certain range of excitation parameters. These dynamic structures emerge as a result of the competition between magnetic and hydrodynamic forces and have complex unconventional magnetic ordering. Nontrivial self-induced hydrodynamic fields accompany each out-of-equilibrium pattern. Spontaneous symmetry breaking of the self-induced surface flows leading to a formation of self-propelled microstructures has been discovered. Some features of the self-localized structures can be understood in the framework of the amplitude equation (Ginzburg-Landau type equation) for parametric waves coupled to the conservation law equation describing the evolution of the magnetic particle density and the Navier-Stokes equation for hydrodynamic flows. To understand the fundamental microscopic mechanisms governing self-assembly processes in magnetic colloidal dispersions at liquid-air interfaces a first-principle model for a non-equilibrium self-assembly is presented. The latter model allows us to capture in detail the entire process of out-of-equilibrium self-assembly in the system and reproduces most of the observed phenomenology. (topical review)

Transition of W7-X non-planar coils from manufacturing to assembly

Energy Technology Data Exchange (ETDEWEB)

Ehrke, G. [Max-Planck-Institut fuer Plasmaphysik (IPP), EURATOM Association, Wendelsteinstrasse 1, D-17491 Greifswald (Germany)], E-mail: gunnar.ehrke@ipp.mpg.de

2009-06-15

The main magnetic field of Wendelstein 7-X fusion experiment (W7-X) at Max-Planck-Institut fuer Plasmaphysik Greifswald, Germany will be provided by 50 non-planar coils and supported by 20 planar coils. The non-planar coils were delivered by a consortium (CON) consisting of Babcock Noell GmbH Germany (BNG) and ASG Superconductors S.p.A. Italy (ASG). The coil production ended with the delivery of the last non-planar coil in March 2008 at the manufacturing branch of BNG in Zeitz, Germany. The construction of the coils was characterised by design changes, many rework actions and resulting time delays. Due to these numerous adjustments and changes a continuous improvement process was needed. This paper will give an overview about the transition of the non-planar coils from the acceptance tests at the manufacturer site to the beginning of the assembly at IPP. Furthermore this report will highlight technical interfaces in the period of transition.

Computational and theoretical modeling of pH and flow effects on the early-stage non-equilibrium self-assembly of optoelectronic peptides

Science.gov (United States)

Mansbach, Rachael; Ferguson, Andrew

Self-assembling π-conjugated peptides are attractive candidates for the fabrication of bioelectronic materials possessing optoelectronic properties due to electron delocalization over the conjugated peptide groups. We present a computational and theoretical study of an experimentally-realized optoelectronic peptide that displays triggerable assembly in low pH to resolve the microscopic effects of flow and pH on the non-equilibrium morphology and kinetics of assembly. Using a combination of molecular dynamics simulations and hydrodynamic modeling, we quantify the time and length scales at which convective flows employed in directed assembly compete with microscopic diffusion to influence assembly. We also show that there is a critical pH below which aggregation proceeds irreversibly, and quantify the relationship between pH, charge density, and aggregate size. Our work provides new fundamental understanding of pH and flow of non-equilibrium π-conjugated peptide assembly, and lays the groundwork for the rational manipulation of environmental conditions and peptide chemistry to control assembly and the attendant emergent optoelectronic properties. This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award # DE-SC0011847, and by the Computational Science and Engineering Fellowship from the University of Illinois at Urbana-Champaign.

Cycling performance of lithium polymer cells assembled by in situ polymerization of a non-flammable ionic liquid monomer

International Nuclear Information System (INIS)

Lee, Yoon-Sung; Kim, Dong-Won

2013-01-01

Highlights: • Gel polymer electrolytes were synthesized by in situ polymerization of ionic liquid in the lithium polymer cells. • Flammability of the electrolyte was significantly reduced by polymerizing electrolyte containing a non-flammable ionic liquid monomer. • The cells assembled with polymeric ionic liquid-based electrolytes exhibited reversible cycling behavior with good capacity retention. -- Abstract: Lithium polymer cells composed of a lithium negative electrode and a LiCoO 2 positive electrode were assembled with a gel polymer electrolyte obtained by in situ polymerization of an electrolyte solution containing an ionic liquid monomer with vinyl groups. The polymerization of the electrolyte solution containing the non-flammable ionic liquid monomer resulted in a significant reduction of the flammability of the gel polymer electrolytes. The lithium polymer cell assembled with the stable gel polymer electrolyte delivered a discharge capacity of 134.3 mAh g −1 at ambient temperature and exhibited good capacity retention

Effects of non-latching blast valves on the source term and consequences of the design-basis accidents in the Device Assembly Facility (DAF)

International Nuclear Information System (INIS)

Nguyen, D.H.

1993-08-01

The analysis of the Design-Basis Accidents (DBA) involving high explosives (HE) and Plutonium (Pu) in the assembly cell of the Device Assembly Facility (DAF), which was completed earlier, assumed latching blast valves in the ventilation system of the assembly cell. Latching valves effectively sealed a release path through the ventilation duct system. However, the blast valves in the assembly cell, as constructed are actually non-latching valves, and would reopen when the gas pressure drops to 0.5 psi above one atmosphere. Because the reopening of the blast valves provides an additional release path to the environment, and affects the material transport from the assembly cell to other DAF buildings, the DOE/NV DAF management has decided to support an additional analysis of the DAF's DBA to account for the effects of non-latching valves. Three cases were considered in the DAF's DBA, depending on the amount of HE and Pu involved, as follows: Case 1 -- 423 number-sign HE, 16 kg Pu; Case 2 -- 150 number-sign HE 10 kg Pu; Case 3 -- 55 number-sign HE 5 kg Pu. The results of the analysis with non-latching valves are summarized

Quantitative RNA-Seq analysis in non-model species: assessing transcriptome assemblies as a scaffold and the utility of evolutionary divergent genomic reference species

Directory of Open Access Journals (Sweden)

Hornett Emily A

2012-08-01

Full Text Available Abstract Background How well does RNA-Seq data perform for quantitative whole gene expression analysis in the absence of a genome? This is one unanswered question facing the rapidly growing number of researchers studying non-model species. Using Homo sapiens data and resources, we compared the direct mapping of sequencing reads to predicted genes from the genome with mapping to de novo transcriptomes assembled from RNA-Seq data. Gene coverage and expression analysis was further investigated in the non-model context by using increasingly divergent genomic reference species to group assembled contigs by unique genes. Results Eight transcriptome sets, composed of varying amounts of Illumina and 454 data, were assembled and assessed. Hybrid 454/Illumina assemblies had the highest transcriptome and individual gene coverage. Quantitative whole gene expression levels were highly similar between using a de novo hybrid assembly and the predicted genes as a scaffold, although mapping to the de novo transcriptome assembly provided data on fewer genes. Using non-target species as reference scaffolds does result in some loss of sequence and expression data, and bias and error increase with evolutionary distance. However, within a 100 million year window these effect sizes are relatively small. Conclusions Predicted gene sets from sequenced genomes of related species can provide a powerful method for grouping RNA-Seq reads and annotating contigs. Gene expression results can be produced that are similar to results obtained using gene models derived from a high quality genome, though biased towards conserved genes. Our results demonstrate the power and limitations of conducting RNA-Seq in non-model species.

A practical guide to build de-novo assemblies for single tissues of non-model organisms: the example of a Neotropical frog

Directory of Open Access Journals (Sweden)

Santiago Montero-Mendieta

2017-09-01

Full Text Available Whole genome sequencing (WGS is a very valuable resource to understand the evolutionary history of poorly known species. However, in organisms with large genomes, as most amphibians, WGS is still excessively challenging and transcriptome sequencing (RNA-seq represents a cost-effective tool to explore genome-wide variability. Non-model organisms do not usually have a reference genome and the transcriptome must be assembled de-novo. We used RNA-seq to obtain the transcriptomic profile for Oreobates cruralis, a poorly known South American direct-developing frog. In total, 550,871 transcripts were assembled, corresponding to 422,999 putative genes. Of those, we identified 23,500, 37,349, 38,120 and 45,885 genes present in the Pfam, EggNOG, KEGG and GO databases, respectively. Interestingly, our results suggested that genes related to immune system and defense mechanisms are abundant in the transcriptome of O. cruralis. We also present a pipeline to assist with pre-processing, assembling, evaluating and functionally annotating a de-novo transcriptome from RNA-seq data of non-model organisms. Our pipeline guides the inexperienced user in an intuitive way through all the necessary steps to build de-novo transcriptome assemblies using readily available software and is freely available at: https://github.com/biomendi/TRANSCRIPTOME-ASSEMBLY-PIPELINE/wiki.

De novo transcriptome assembly for a non-model species, the blood-sucking bug Triatoma brasiliensis, a vector of Chagas disease.

Science.gov (United States)

Marchant, A; Mougel, F; Almeida, C; Jacquin-Joly, E; Costa, J; Harry, M

2015-04-01

High throughput sequencing (HTS) provides new research opportunities for work on non-model organisms, such as differential expression studies between populations exposed to different environmental conditions. However, such transcriptomic studies first require the production of a reference assembly. The choice of sampling procedure, sequencing strategy and assembly workflow is crucial. To develop a reliable reference transcriptome for Triatoma brasiliensis, the major Chagas disease vector in Northeastern Brazil, different de novo assembly protocols were generated using various datasets and software. Both 454 and Illumina sequencing technologies were applied on RNA extracted from antennae and mouthparts from single or pooled individuals. The 454 library yielded 278 Mb. Fifteen Illumina libraries were constructed and yielded nearly 360 million RNA-seq single reads and 46 million RNA-seq paired-end reads for nearly 45 Gb. For the 454 reads, we used three assemblers, Newbler, CAP3 and/or MIRA and for the Illumina reads, the Trinity assembler. Ten assembly workflows were compared using these programs separately or in combination. To compare the assemblies obtained, quantitative and qualitative criteria were used, including contig length, N50, contig number and the percentage of chimeric contigs. Completeness of the assemblies was estimated using the CEGMA pipeline. The best assembly (57,657 contigs, completeness of 80 %, <1 % chimeric contigs) was a hybrid assembly leading to recommend the use of (1) a single individual with large representation of biological tissues, (2) merging both long reads and short paired-end Illumina reads, (3) several assemblers in order to combine the specific advantages of each.

Molecular mechanism of protein assembly on DNA double-strand breaks in the non-homologous end-joining pathway

International Nuclear Information System (INIS)

Yano, Ken-ichi; Morotomi-Yano, Keiko; Adachi, Noritaka; Akiyama, Hidenori

2009-01-01

Non-homologous end-joining (NHEJ) is the major repair pathway for DNA double-strand breaks (DSBs) in mammalian species. Upon DSB induction, a living cell quickly activates the NHEJ pathway comprising of multiple molecular events. However, it has been difficult to analyze the initial phase of DSB responses in living cells, primarily due to technical limitations. Recent advances in real-time imaging and site-directed DSB induction using laser microbeam allow us to monitor the spatiotemporal dynamics of NHEJ factors in the immediate-early phase after DSB induction. These new approaches, together with the use of cell lines deficient in each essential NHEJ factor, provide novel mechanistic insights into DSB recognition and protein assembly on DSBs in the NHEJ pathway. In this review, we provide an overview of recent progresses in the imaging analyses of the NHEJ core factors. These studies strongly suggest that the NHEJ core factors are pre-assembled into a large complex on DSBs prior to the progression of the biochemical reactions in the NHEJ pathway. Instead of the traditional step-by-step assembly model from the static view of NHEJ, a novel model for dynamic protein assembly in the NHEJ pathway is proposed. This new model provides important mechanistic insights into the protein assembly at DSBs and the regulation of DSB repair. (author)

A universal molecular translator for non-nucleic acid targets that enables dynamic DNA assemblies and logic operations.

Science.gov (United States)

Tang, Wei; Hu, Shichao; Wang, Huaming; Zhao, Yan; Li, Na; Liu, Feng

2014-11-28

A universal molecular translator based on the target-triggered DNA strand displacement was developed, which was able to convert various kinds of non-nucleic acid targets into a unique output DNA. This translation strategy was successfully applied in directing dynamic DNA assemblies and in realizing three-input logic gate operations.

Consequences of Molecular-Scale Non-Equilibrium Activity on the Dynamics and Mechanics of Self-Assembled Actin-Based Structures and Materials

Science.gov (United States)

Marshall Mccall, Patrick

Living cells are hierarchically self-organized forms of active soft matter: molecules on the nanometer scale form functional structures and organelles on the micron scale, which then compose cells on the scale of 10s of microns. While the biological functions of intracellular organelles are defined by the composition and properties of the structures themselves, how those bulk properties emerge from the properties and interactions of individual molecules remains poorly understood. Actin, a globular protein which self-assembles into dynamic semi-flexible polymers, is the basic structural material of cells and the major component of many functional organelles. In this thesis, I have used purified actin as a model system to explore the interplay between molecular-scale dynamics and organelle-scale functionality, with particular focus on the role of molecular-scale non-equilibrium activity. One of the most canonical forms of molecular-scale non-equilibrium activity is that of mechanoenzymes, also called motor proteins. These proteins utilized the free energy liberated by hydrolysis of ATP to perform mechanical work, thereby introducing non-equilibrium "active" stresses on the molecular scale. Combining experiments with mathematical modeling, we demonstrate in this thesis that non-equilibrium motor activity is sufficient to drive self-organization and pattern formation of the multimeric actin-binding motor protein Myosin II on 1D reconstituted actomyosin bundles. Like myosin, actin is itself an ATPase. However, nono-equilibrium ATP hydrolysis on actin is known to regulate the stability and assembly kinetics of actin filaments rather than generate active stresses per se. At the level of single actin filaments, the inhomogeneous nucleotide composition generated along the filament length by hydrolysis directs binding of regulatory proteins like cofilin, which mediate filament disassembly and thereby accelerate actin filament turnover. The concequences of this non

Mechanical seal assembly

Science.gov (United States)

Kotlyar, Oleg M.

2001-01-01

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Mechanical Seal Assembly

Energy Technology Data Exchange (ETDEWEB)

Kotlyar, Oleg M.

1999-06-18

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Harnessing natural product assembly lines: structure, promiscuity, and engineering.

Science.gov (United States)

Ladner, Christopher C; Williams, Gavin J

2016-03-01

Many therapeutically relevant natural products are biosynthesized by the action of giant mega-enzyme assembly lines. By leveraging the specificity, promiscuity, and modularity of assembly lines, a variety of strategies has been developed that enables the biosynthesis of modified natural products. This review briefly summarizes recent structural advances related to natural product assembly lines, discusses chemical approaches to probing assembly line structures in the absence of traditional biophysical data, and surveys efforts that harness the inherent or engineered promiscuity of assembly lines for the synthesis of non-natural polyketides and non-ribosomal peptide analogues.

deepening decentralisation through non-partisan district assembly ...

African Journals Online (AJOL)

PUBLICATIONS1

-depth analysis of the legal framework within which decentralisation reforms are implemented was also ... country's democracy, the legal framework need to be revised for competitive partisan elections to be pursued ..... the quality of debates in the general Assembly will be poor as .... Coleman, J. S. (Eds.) Social Theory for a.

The use of HANDIDET reg-sign non-electric detonator assemblies to reduce blast-induced overpressure at AECL's Underground Research Laboratory

International Nuclear Information System (INIS)

Onagi, D.P.; Keith, S.G.; Kuzyk, G.W.

1996-01-01

A number of aspects of the Canadian concept for nuclear fuel waste disposal are being assessed by Atomic Energy of Canada Limited (AECL) in a series of experiments at its Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, Canada. One of the major objectives of the work being carried out at the URL is to develop and evaluate the methods and technology to ensure safe, permanent disposal of Canada's nuclear fuel waste. In 1994, AECL excavated access tunnels and a laboratory room for the Quarried Block Fracture Migration Experiment (QBFME) at the 240 Level of the URL. This facility will be used to study the transport of radionuclides in natural fractures in quarried blocks of granite under in-situ groundwater conditions. The experiment is being carried out under a cooperative agreement with the Japan Atomic Energy Research Institute. The excavation of the QBFME access tunnels and laboratory was carried out using controlled blasting techniques that minimized blast-induced overpressure which could have damaged or interrupted other ongoing experiments in the vicinity. The majority of the blasts used conventional long delay non-electric detonators but a number of blasts were carried out using HANDIDET 250/6000 non-electric long delay detonator assemblies and HTD reg-sign non-electric short delay trunkline detonator assemblies. The tunnel and laboratory excavation was monitored to determine the levels of blast-induced overpressure. This paper describes the blasting and monitoring results of the blasts using HANDIDET non-electric detonator assemblies and the effectiveness of these detonators in reducing blast-induced overpressure

Robust, directed assembly of fluorescent nanodiamonds.

Science.gov (United States)

Kianinia, Mehran; Shimoni, Olga; Bendavid, Avi; Schell, Andreas W; Randolph, Steven J; Toth, Milos; Aharonovich, Igor; Lobo, Charlene J

2016-10-27

Arrays of fluorescent nanoparticles are highly sought after for applications in sensing, nanophotonics and quantum communications. Here we present a simple and robust method of assembling fluorescent nanodiamonds into macroscopic arrays. Remarkably, the yield of this directed assembly process is greater than 90% and the assembled patterns withstand ultra-sonication for more than three hours. The assembly process is based on covalent bonding of carboxyl to amine functional carbon seeds and is applicable to any material, and to non-planar surfaces. Our results pave the way to directed assembly of sensors and nanophotonics devices.

Harnessing NGS and Big Data Optimally: Comparison of miRNA Prediction from Assembled versus Non-assembled Sequencing Data--The Case of the Grass Aegilops tauschii Complex Genome.

Science.gov (United States)

Budak, Hikmet; Kantar, Melda

2015-07-01

MicroRNAs (miRNAs) are small, endogenous, non-coding RNA molecules that regulate gene expression at the post-transcriptional level. As high-throughput next generation sequencing (NGS) and Big Data rapidly accumulate for various species, efforts for in silico identification of miRNAs intensify. Surprisingly, the effect of the input genomics sequence on the robustness of miRNA prediction was not evaluated in detail to date. In the present study, we performed a homology-based miRNA and isomiRNA prediction of the 5D chromosome of bread wheat progenitor, Aegilops tauschii, using two distinct sequence data sets as input: (1) raw sequence reads obtained from 454-GS FLX Titanium sequencing platform and (2) an assembly constructed from these reads. We also compared this method with a number of available plant sequence datasets. We report here the identification of 62 and 22 miRNAs from raw reads and the assembly, respectively, of which 16 were predicted with high confidence from both datasets. While raw reads promoted sensitivity with the high number of miRNAs predicted, 55% (12 out of 22) of the assembly-based predictions were supported by previous observations, bringing specificity forward compared to the read-based predictions, of which only 37% were supported. Importantly, raw reads could identify several repeat-related miRNAs that could not be detected with the assembly. However, raw reads could not capture 6 miRNAs, for which the stem-loops could only be covered by the relatively longer sequences from the assembly. In summary, the comparison of miRNA datasets obtained by these two strategies revealed that utilization of raw reads, as well as assemblies for in silico prediction, have distinct advantages and disadvantages. Consideration of these important nuances can benefit future miRNA identification efforts in the current age of NGS and Big Data driven life sciences innovation.

Non-enzymatic glucose sensing platform using self assembled cobalt oxide/graphene nanocomposites immobilized graphite modified electrode

DEFF Research Database (Denmark)

Vivekananth, R.; Babu, R. Suresh; Prasanna, K.

2018-01-01

A new strategy to prepare the densely packed cobalt oxide (Co3O4)/graphene nanocomposites by a self-assembly method were adopted in this work. A new non-enzymatic glucose determination has been fabricated by using Co3O4/graphene nanocomposites modified electrode as a sensing material. The nanocom...... of the modified electrode for glucose determination has been evaluated in urine samples....

Evaluation of the fuel-element assembly non-hermeticity at its early stage

International Nuclear Information System (INIS)

Bliznyakova, V.A.; Shevel', V.N.; Ostapenko, V.I.

1983-01-01

The given paper deals with control of the fuel-element assembly shell state at the early stage of failure development. Technique for the fuel-element assembly shell state evaluation are described. A method for assembly failure detection, used at WWR of the Institute for Nuclear Research is described also

The Assembly of Cell-Encapsulating Microscale Hydrogels Using Acoustic Waves

Science.gov (United States)

Xu, Feng; Finley, Thomas Dylan; Turkaydin, Muge; Sung, Yuree; Gurkan, Umut Atakan; Yavuz, Ahmet Sinan; Guldiken, Rasim; Demirci, Utkan

2011-01-01

Microscale hydrogels find widespread applications in medicine and biology, e.g., as building blocks for tissue engineering and regenerative medicine. In these applications, these microgels are assembled to fabricate large complex 3D constructs. The success of this approach requires non-destructive and high throughput assembly of the microgels. Although various assembly methods have been developed based on modifying interfaces, and using microfluidics, so far, none of the available assembly technologies have shown the ability to assembly microgels using non-invasive fields rapidly within seconds in an efficient way. Acoustics has been widely used in biomedical area to manipulatedroplets, cells and biomolecules. In this study, we developed a simple, non-invasiveacoustic assembler for cell-encapsulating microgels with maintained cell viability (>93%). We assessed the assembler for both microbeads (with diameter of 50 µm and 100 µm) and microgels of different sizes and shapes (e.g., cubes, lock-and-key shapes, tetris, saw) in microdroplets (with volume of 10 µL, 20 µL, 40 µL, 80 µL). The microgels were assembled in second sin a non-invasive manner. These results indicate that the developed acoustic approach could become an enabling biotechnology tool for tissue engineering, regenerative medicine, pharmacology studies and high throughput screening applications. PMID:21820734

Effect of absorption discontinuity on neutron spectra of water assemblies poisoned with non-1/V absorbers

International Nuclear Information System (INIS)

Gupta, I.J.; Trikha, S.K.

1977-01-01

Calculations are presented of the diffusion of thermal neutrons (2.5 x 10 -4 to 7 x 10 -1 eV) across an absorption discontinuity in a water assembly, consisting of pure water on one side and aqueous solutions of three different non-1/V absorbers on the other, which were obtained by solving the Boltzmann transport equation in the diffusion approximation using the multigroup formalism. The gradual appearance and disappearance of the depletion region in the neutron spectra (caused by the resonance absorption peaks at energies 0.096 and 0.179 eV for samarium and cadmium respectively), as one moves from the pure water assembly to the poisoned water assembly and vice versa, have also been studied. The minimum concentrations of Sm and Cd atoms in water for which the depletion region in the spectra just starts building up are found to be 60 x 10 18 Sm atom cm -3 and 125 x 10 18 Cd atom cm -3 respectively. However no such depletion region is observed in gadolinium-poisoned water assembly. At the boundary, the equilibrium neutron distribution gets disturbed and is re-established to the equilibrium distribution of the second medium at some distance from the interface. The diffusion lengths so calculated from the total neutron density curves are in good agreement with the experimental results of Goddard and Johnson (Nucl. Sci. Eng.; 37:127 (1969)) at various concentrations of Gd and Cd atoms in water. (author)

Non-volatile flash memory with discrete bionanodot floating gate assembled by protein template

International Nuclear Information System (INIS)

Miura, Atsushi; Yamashita, Ichiro; Uraoka, Yukiharu; Fuyuki, Takashi; Tsukamoto, Rikako; Yoshii, Shigeo

2008-01-01

We demonstrated non-volatile flash memory fabrication by utilizing uniformly sized cobalt oxide (Co 3 O 4 ) bionanodot (Co-BND) architecture assembled by a cage-shaped supramolecular protein template. A fabricated high-density Co-BND array was buried in a metal-oxide-semiconductor field-effect-transistor (MOSFET) structure to use as the charge storage node of a floating nanodot gate memory. We observed a clockwise hysteresis in the drain current-gate voltage characteristics of fabricated BND-embedded MOSFETs. Observed hysteresis obviously indicates a memory operation of Co-BND-embedded MOSFETs due to the charge confinement in the embedded BND and successful functioning of embedded BNDs as the charge storage nodes of the non-volatile flash memory. Fabricated Co-BND-embedded MOSFETs showed good memory properties such as wide memory windows, long charge retention and high tolerance to repeated write/erase operations. A new pathway for device fabrication by utilizing the versatile functionality of biomolecules is presented

The use of HANDIDET{reg_sign} non-electric detonator assemblies to reduce blast-induced overpressure at AECL`s Underground Research Laboratory

Energy Technology Data Exchange (ETDEWEB)

Onagi, D.P.; Keith, S.G.; Kuzyk, G.W. [AECL, Pinawa, Manitoba (Canada). Underground Research Lab.; Proudfoot, D.F. [ICI Explosives Canada, North Delta, British Columbia (Canada)

1996-12-01

A number of aspects of the Canadian concept for nuclear fuel waste disposal are being assessed by Atomic Energy of Canada Limited (AECL) in a series of experiments at its Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, Canada. One of the major objectives of the work being carried out at the URL is to develop and evaluate the methods and technology to ensure safe, permanent disposal of Canada`s nuclear fuel waste. In 1994, AECL excavated access tunnels and a laboratory room for the Quarried Block Fracture Migration Experiment (QBFME) at the 240 Level of the URL. This facility will be used to study the transport of radionuclides in natural fractures in quarried blocks of granite under in-situ groundwater conditions. The experiment is being carried out under a cooperative agreement with the Japan Atomic Energy Research Institute. The excavation of the QBFME access tunnels and laboratory was carried out using controlled blasting techniques that minimized blast-induced overpressure which could have damaged or interrupted other ongoing experiments in the vicinity. The majority of the blasts used conventional long delay non-electric detonators but a number of blasts were carried out using HANDIDET 250/6000 non-electric long delay detonator assemblies and HTD{reg_sign} non-electric short delay trunkline detonator assemblies. The tunnel and laboratory excavation was monitored to determine the levels of blast-induced overpressure. This paper describes the blasting and monitoring results of the blasts using HANDIDET non-electric detonator assemblies and the effectiveness of these detonators in reducing blast-induced overpressure.

Seismic behaviour of fuel assembly

Energy Technology Data Exchange (ETDEWEB)

Song, Heuy Gap; Jhung, Myung Jo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1993-11-01

A general approach for the dynamic time-history analysis of the reactor core is presented in this paper as a part of the fuel assembly qualification program. Several detailed core models are set up to reflect the placement of the fuel assemblies within the core shroud. Peak horizontal responses are obtained for each model for the motions induced from earthquake. The dynamic responses such as fuel assembly shear force, bending moment and displacement, and spacer grid impact loads are carefully investigated. Also, the sensitivity responses are obtained for the earthquake motions and the fuel assembly non-linear response characteristics are discussed. (Author) 9 refs., 24 figs., 1 tab.

Self-assembly of coiled coil peptides into nanoparticles vs 2-d plates: effects of assembly pathway

Science.gov (United States)

Kim, Kyunghee; Pochan, Darrin

Molecular solution assembly, or self-assembly, is a process by which ordered nanostructures or patterns are formed by non-covalent interactions during assembly. Biomimicry, the use of bioinspired molecules or biologically relevant materials, is an important area of self-assembly research with peptides serving a critical role as molecular tools. The morphology of peptide assemblies can be controlled by adjusting solution conditions such as the concentration of peptides, the temperature, and pH. Herein, spherical nanostructures, which have potential for creating an encapsulation system, are formed by self-assembly when coiled coil peptides are combined in solution. These peptides are homotrimeric and heterodimeric coiled-coil bundles and the homotrimer is connected with each of heterodimer through their external surfaces via disulfide bonds. The resultant covalent constructs could co-assemble into complementary trimeric hubs, respectively. The two peptide constructs are directly mixed and assembled in solution in order to produce either spherical particles or 2-d plates depending on the solution conditions and kinetic pathway of assembly. In particular, structural changes of the self-assembled peptides are explored by control of the thermal history of the assembly solution.

Methods of making membrane electrode assemblies

Science.gov (United States)

Kim, Yu Seung; Lee, Kwan -Soo; Rockward, Tommy Q. T.

2015-07-28

Method of making a membrane electrode assembly comprising: providing a membrane comprising a perfluorinated sulfonic acid; providing a first transfer substrate; applying to a surface of the first transfer substrate a first ink, said first ink comprising an ionomer and a catalyst; applying to the first ink a suitable non-aqueous swelling agent; forming an assembly comprising: the membrane; and the first transfer substrate, wherein the surface of the first transfer substrate comprising the first ink and the non-aqueous swelling agent is disposed upon one surface of the membrane; and heating the assembly at a temperature of 150.degree. C. or less and at a pressure of from about 250 kPa to about 3000 kPa or less for a time suitable to allow substantially complete transfer of the first ink and the second ink to the membrane; and cooling the assembly to room temperature and removing the first transfer substrate and the second transfer substrate.

De Novo Assembly of Complete Chloroplast Genomes from Non-model Species Based on a K-mer Frequency-Based Selection of Chloroplast Reads from Total DNA Sequences

Directory of Open Access Journals (Sweden)

Shairul Izan

2017-08-01

Full Text Available Whole Genome Shotgun (WGS sequences of plant species often contain an abundance of reads that are derived from the chloroplast genome. Up to now these reads have generally been identified and assembled into chloroplast genomes based on homology to chloroplasts from related species. This re-sequencing approach may select against structural differences between the genomes especially in non-model species for which no close relatives have been sequenced before. The alternative approach is to de novo assemble the chloroplast genome from total genomic DNA sequences. In this study, we used k-mer frequency tables to identify and extract the chloroplast reads from the WGS reads and assemble these using a highly integrated and automated custom pipeline. Our strategy includes steps aimed at optimizing assemblies and filling gaps which are left due to coverage variation in the WGS dataset. We have successfully de novo assembled three complete chloroplast genomes from plant species with a range of nuclear genome sizes to demonstrate the universality of our approach: Solanum lycopersicum (0.9 Gb, Aegilops tauschii (4 Gb and Paphiopedilum henryanum (25 Gb. We also highlight the need to optimize the choice of k and the amount of data used. This new and cost-effective method for de novo short read assembly will facilitate the study of complete chloroplast genomes with more accurate analyses and inferences, especially in non-model plant genomes.

Detailed channel thermal-hydraulic calculation of nuclear reactor fuel assemblies

International Nuclear Information System (INIS)

Zhukov, A.V.; Sorokin, A.P.; Ushakov, P.A.; Yur'ev, Yu.S.

1981-01-01

The system of equations of mass balance, quantity of motion and energy used in calculation of nuclear reactor fuel assemblies is obtained. The equation system is obtained on the base of integral equations of hydrodynamics interaction in assemblies of smooth fuel elements and fuel elements with wire packing. The calculation results of coolant heating distributions by the fast reactor assembly channels are presented. The analysis of the results obtained shows that interchannel exchange essentially uniforms the coolant heating distribution in the peripheral range of the assembly but it does not remove non-uniformity caused by power distribution non-uniformity in the cross section. Geometry of the peripheral assembly range plays an essential role in the heating distribution. Change of the calculation gap between the peripheral fuel elements and assembly shells can result either in superheating or in subcooling in the peripheral channels relatively to joint internal channels of the assembly. Heat supply to the coolant passing through interassembly gaps decreases temperature in the assembly periphery and results in the increase of temperature non-uniformity by the perimeter of peripheral fuel elements. It is concluded that the applied method of the channel-by-channel calculation is ef-- fective in thermal-physical calculation of nuclear reactor fuel assemblies and it permits to solve a wide range of problems [ru

Method for assembling dynamoelectric machine end shield parts

International Nuclear Information System (INIS)

Thomson, J.M.

1984-01-01

Methods, apparatus, and systems are provided for automatically assembling end shield assemblies of subassemblies for electric motors. In a preferred form, a system and methods are provided that utilize a non-palletized, non-synchronous concept to convey end shields through a number of assembly stations. At process stations situated along a conveyor, operations are performed on components. One method includes controlling traffic of sub-assemblies by toggle type escapements. A stop or latch of unique design stops end shield components in midstream, and ''lifts'' of unique design disengage parts from the conveyor and also support such parts during various operations. Photo-optic devices and proximity and reed switch mechanisms are utilized for control purposes. The work stations involved in one system include a unique assembly and pressing station involving oil well covers; a unique feed wick seating system; a unique lubricant adding operation; and unique ''building block'' mechanisms and methods

TESS Lens-Bezel Assembly Modal Testing

Science.gov (United States)

Dilworth, Brandon J.; Karlicek, Alexandra

2017-01-01

The Transiting Exoplanet Survey Satellite (TESS) program, led by the Kavli Institute for Astrophysics and Space Research at the Massachusetts Institute of Technology (MIT) will be the first-ever spaceborne all-sky transit survey. MIT Lincoln Laboratory is responsible for the cameras, including the lens assemblies, detector assemblies, lens hoods, and camera mounts. TESS is scheduled to be launched in August of 2017 with the primary goal to detect small planets with bright host starts in the solar neighborhood, so that detailed characterizations of the planets and their atmospheres can be performed. The TESS payload consists of four identical cameras and a data handling unit. Each camera consists of a lens assembly with seven optical elements and a detector assembly with four charge-coupled devices (CCDs) including their associated electronics. The optical prescription requires that several of the lenses are in close proximity to a neighboring element. A finite element model (FEM) was developed to estimate the relative deflections between each lens-bezel assembly under launch loads to predict that there are adequate clearances preventing the lenses from making contact. Modal tests using non-contact response measurements were conducted to experimentally estimate the modal parameters of the lens-bezel assembly, and used to validate the initial FEM assumptions. Key Words Non-contact measurements, modal analysis, model validation

Self-assembled Nanomaterials for Chemotherapeutic Applications

Science.gov (United States)

Shieh, Aileen

The self-assembly of short designed peptides into functional nanostructures is becoming a growing interest in a wide range of fields from optoelectronic devices to nanobiotechnology. In the medical field, self-assembled peptides have especially attracted attention with several of its attractive features for applications in drug delivery, tissue regeneration, biological engineering as well as cosmetic industry and also the antibiotics field. We here describe the self-assembly of peptide conjugated with organic chromophore to successfully deliver sequence independent micro RNAs into human non-small cell lung cancer cell lines. The nanofiber used as the delivery vehicle is completely non-toxic and biodegradable, and exhibit enhanced permeability effect for targeting malignant tumors. The transfection efficiency with nanofiber as the delivery vehicle is comparable to that of the commercially available RNAiMAX lipofectamine while the toxicity is significantly lower. We also conjugated the peptide sequence with camptothecin (CPT) and observed the self-assembly of nanotubes for chemotherapeutic applications. The peptide scaffold is non-toxic and biodegradable, and drug loading of CPT is high, which minimizes the issue of systemic toxicity caused by extensive burden from the elimination of drug carriers. In addition, the peptide assembly drastically increases the solubility and stability of CPT under physiological conditions in vitro, while active CPT is gradually released from the peptide chain under the slight acidic tumor cell environment. Cytotoxicity results on human colorectal cancer cells and non-small cell lung cancer cell lines display promising anti-cancer properties compared to the parental CPT drug, which cannot be used clinically due to its poor solubility and lack of stability in physiological conditions. Moreover, the peptide sequence conjugated with 5-fluorouracil formed a hydrogel with promising topical chemotherapeutic applications that also display

Non-equilibrium supramolecular polymerization.

Science.gov (United States)

Sorrenti, Alessandro; Leira-Iglesias, Jorge; Markvoort, Albert J; de Greef, Tom F A; Hermans, Thomas M

2017-09-18

Supramolecular polymerization has been traditionally focused on the thermodynamic equilibrium state, where one-dimensional assemblies reside at the global minimum of the Gibbs free energy. The pathway and rate to reach the equilibrium state are irrelevant, and the resulting assemblies remain unchanged over time. In the past decade, the focus has shifted to kinetically trapped (non-dissipative non-equilibrium) structures that heavily depend on the method of preparation (i.e., pathway complexity), and where the assembly rates are of key importance. Kinetic models have greatly improved our understanding of competing pathways, and shown how to steer supramolecular polymerization in the desired direction (i.e., pathway selection). The most recent innovation in the field relies on energy or mass input that is dissipated to keep the system away from the thermodynamic equilibrium (or from other non-dissipative states). This tutorial review aims to provide the reader with a set of tools to identify different types of self-assembled states that have been explored so far. In particular, we aim to clarify the often unclear use of the term "non-equilibrium self-assembly" by subdividing systems into dissipative, and non-dissipative non-equilibrium states. Examples are given for each of the states, with a focus on non-dissipative non-equilibrium states found in one-dimensional supramolecular polymerization.

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Sakurai, Shungo; Ogiya, Shunsuke.

1990-01-01

In a fuel assembly, if the entire fuels comprise mixed oxide fuels, reactivity change in cold temperature-power operation is increased to worsen the reactor shutdown margin. The reactor shutdown margin has been improved by increasing the burnable poison concentration thereby reducing the reactivity of the fuel assembly. However, since unburnt poisons are present at the completion of the reactor operation, the reactivity can not be utilized effectively to bring about economical disadvantage. In view of the above, the reactivity change between lower temperature-power operations is reduced by providing a non-boiling range with more than 9.1% of cross sectional area at the inside of a channel at the central portion of the fuel assembly. As a result, the amount of the unburnt burnable poisons is decreased, the economy of fuel assembly is improved and the reactor shutdown margin can be increase. (N.H.)

DNA controlled assembly of liposomes

DEFF Research Database (Denmark)

Vogel, Stefan; Jakobsen, Ulla; Simonsen, Adam Cohen

2009-01-01

DNA-encoding of solid nanoparticles requires surfacechemistry, which is often tedious and not generally applicable. In the present study non-covalently attached DNA are used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from...... assembled to disassembled state for which reason this method allows easy and fast detection of polynucleotides (e.g. DNA or RNA), including single nucleotide polymorphisms as well as insertions and deletions....

The role of Monte Carlo burnup calculations in quantifying plutonium mass in spent fuel assemblies with non-destructive assay

Energy Technology Data Exchange (ETDEWEB)

Galloway, Jack D.; Tobin, Stephen J.; Trellue, Holly R.; Fensin, Michael L. [Los Alamos National Laboratory, Los Alamos, (United States)

2011-12-15

The Next Generation Safeguards Initiate (NGSI) of the United States Department of Energy has funded a multi-laboratory/university collaboration to quantify plutonium content in spent fuel (SF) with non-destructive assay (NDA) techniques and quantify the capability of these NDA techniques to detect pin diversions from SF assemblies. The first Monte Carlo based spent fuel library (SFL) developed for the NGSI program contained information for 64 different types of SF assemblies (four initial enrichments, burnups, and cooling times). The maximum amount of fission products allowed to still model a 17x17 Westinghouse pressurized water reactor (PWR) fuel assembly with four regions per fuel pin was modelled. The number of fission products tracked was limited by the available memory. Studies have since indicated that additional fission product inclusion and asymmetric burning of the assembly is desired. Thus, an updated SFL has been developed using an enhanced version of MCNPX, more powerful computing resources, and the Monte Carlo-based burnup code Monteburns, which links MCNPX to a depletion code and models a representative 1 Division-Slash 8 core geometry containing one region per fuel pin in the assemblies of interest, including a majority of the fission products with available cross sections. Often in safeguards, the limiting factor in the accuracy of NDA instruments is the quality of the working standard used in calibration. In the case of SF this is anticipated to also be true, particularly for several of the neutron techniques. The fissile isotopes of interest are co-mingled with neutron absorbers that alter the measured count rate. This paper will quantify how well working standards can be generated for PWR spent fuel assemblies and also describe the spatial plutonium distribution across an assembly. More specifically we will demonstrate how Monte Carlo gamma measurement simulations and a Monte Carlo burnup code can be used to characterize the emitted gamma

Correction: An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells.

Science.gov (United States)

Payne, Abby-Jo; Li, Shi; Dayneko, Sergey V; Risko, Chad; Welch, Gregory C

2017-09-21

Correction for 'An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells' by Abby-Jo Payne et al., Chem. Commun., 2017, 53, 10168-10171.

Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1

Energy Technology Data Exchange (ETDEWEB)

Karttunen, Jenni; Mäntynen, Sari [Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä (Finland); Ihalainen, Teemu O. [Stem Cells in Neurological Applications Group, BioMediTech, University of Tampere, Tampere (Finland); Bamford, Jaana K.H. [Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä (Finland); Oksanen, Hanna M., E-mail: hanna.oksanen@helsinki.fi [Institute of Biotechnology and Department of Biosciences, University of Helsinki, Biocenter 2, P.O. Box 56 (Viikinkaari 5), FIN-00014 Helsinki (Finland)

2015-08-15

Bacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diffusion of the P33 fluorescent fusion protein was substantially slower in E. coli than theoretically calculated, presumably resulting from intermolecular interactions. Our results indicate that P33 and P17 function in procapsid assembly, possibly in association with the host chaperonin complex GroEL/GroES. - Highlights: • Two non-structural proteins of PRD1 are involved in the virus assembly. • P17 and P33 complement the defect in GroES of Escherichia coli. • P33 co-localises with GroEL and P17 in the bacterium. • Slow motion of P33 in the bacterium suggests association with cellular components.

NEDDylation promotes stress granule assembly.

Science.gov (United States)

Jayabalan, Aravinth Kumar; Sanchez, Anthony; Park, Ra Young; Yoon, Sang Pil; Kang, Gum-Yong; Baek, Je-Hyun; Anderson, Paul; Kee, Younghoon; Ohn, Takbum

2016-07-06

Stress granules (SGs) harbour translationally stalled messenger ribonucleoproteins and play important roles in regulating gene expression and cell fate. Here we show that neddylation promotes SG assembly in response to arsenite-induced oxidative stress. Inhibition or depletion of key components of the neddylation machinery concomitantly inhibits stress-induced polysome disassembly and SG assembly. Affinity purification and subsequent mass-spectrometric analysis of Nedd8-conjugated proteins from translationally stalled ribosomal fractions identified ribosomal proteins, translation factors and RNA-binding proteins (RBPs), including SRSF3, a previously known SG regulator. We show that SRSF3 is selectively neddylated at Lys85 in response to arsenite. A non-neddylatable SRSF3 (K85R) mutant do not prevent arsenite-induced polysome disassembly, but fails to support the SG assembly, suggesting that the neddylation pathway plays an important role in SG assembly.

A versatile strategy towards non-covalent functionalization of graphene by surface-confined supramolecular self-assembly of Janus tectons

Directory of Open Access Journals (Sweden)

Ping Du

2015-03-01

Full Text Available Two-dimensional (2D, supramolecular self-assembly at surfaces is now well-mastered with several existing examples. However, one remaining challenge to enable future applications in nanoscience is to provide potential functionalities to the physisorbed adlayer. This work reviews a recently developed strategy that addresses this key issue by taking advantage of a new concept, Janus tecton materials. This is a versatile, molecular platform based on the design of three-dimensional (3D building blocks consisting of two faces linked by a cyclophane-type pillar. One face is designed to steer 2D self-assembly onto C(sp2-carbon-based flat surfaces, the other allowing for the desired functionality above the substrate with a well-controlled lateral order. In this way, it is possible to simultaneously obtain a regular, non-covalent paving as well as supramolecular functionalization of graphene, thus opening interesting perspectives for nanoscience applications.

Premixer assembly for mixing air and fuel for combustion

Science.gov (United States)

York, William David; Johnson, Thomas Edward; Keener, Christopher Paul

2016-12-13

A premixer assembly for mixing air and fuel for combustion includes a plurality of tubes disposed at a head end of a combustor assembly. Also included is a tube of the plurality of tubes, the tube including an inlet end and an outlet end. Further included is at least one non-circular portion of the tube extending along a length of the tube, the at least one non-circular portion having a non-circular cross-section, and the tube having a substantially constant cross-sectional area along its length

Biosynthesis: Reprogramming assembly lines

Science.gov (United States)

Menon, Binuraj R. K.; Jenner, Matthew

2018-03-01

Rational engineering of biosynthetic assembly lines for production of new compounds is an attractive prospect, yet it presents many challenges. Learning from biology, some of the rules for expanding the chemical diversity of non-ribosomal peptides have been uncovered in two recent studies.

Flexible Assembly Solar Technology (FAST) Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Toister, Elad [BrightSource Energy Inc., Jerusalem (Israel)

2014-11-06

The Flexible Assembly Solar Technology (FAST) project was initiated by BrightSource in an attempt to provide potential solar field EPC contractors with an effective set of tools to perform specific construction tasks. These tasks are mostly associated with heliostat assembly and installation, and require customized non-standard tools. The FAST concept focuses on low equipment cost, reduced setup time and increased assembly throughput as compared to the Ivanpah solar field construction tools.

The PprA-PprB two-component system activates CupE, the first non-archetypal Pseudomonas aeruginosa chaperione-usher pathway system assembling fimbriae

DEFF Research Database (Denmark)

Giraud, Caroline; Bernard, Christophe S.; Calderon, Virginie

2011-01-01

- and chaperone-encoding genes. This locus, widely conserved in different bacterial species, contains four additional genes encoding non-archetypal fimbrial subunits. We first evidenced that the cupE gene cluster was specifically expressed in biofilm conditions and was responsible for fibre assembly containing...

A divide-and-conquer algorithm for large-scale de novo transcriptome assembly through combining small assemblies from existing algorithms.

Science.gov (United States)

Sze, Sing-Hoi; Parrott, Jonathan J; Tarone, Aaron M

2017-12-06

While the continued development of high-throughput sequencing has facilitated studies of entire transcriptomes in non-model organisms, the incorporation of an increasing amount of RNA-Seq libraries has made de novo transcriptome assembly difficult. Although algorithms that can assemble a large amount of RNA-Seq data are available, they are generally very memory-intensive and can only be used to construct small assemblies. We develop a divide-and-conquer strategy that allows these algorithms to be utilized, by subdividing a large RNA-Seq data set into small libraries. Each individual library is assembled independently by an existing algorithm, and a merging algorithm is developed to combine these assemblies by picking a subset of high quality transcripts to form a large transcriptome. When compared to existing algorithms that return a single assembly directly, this strategy achieves comparable or increased accuracy as memory-efficient algorithms that can be used to process a large amount of RNA-Seq data, and comparable or decreased accuracy as memory-intensive algorithms that can only be used to construct small assemblies. Our divide-and-conquer strategy allows memory-intensive de novo transcriptome assembly algorithms to be utilized to construct large assemblies.

Paired replacement fuel assemblies for BWR-type reactor

International Nuclear Information System (INIS)

Oguchi, Kazushige.

1997-01-01

There are disposed a large-diameter water rod constituting a non-boiling region at a central portion and paired replacement fuel assemblies for two streams having the same average enrichment degree and different amount of burnable poisons. The paired replacement fuel assemblies comprise a first fuel assembly having a less amount of burnable poisons and a second fuel assembly having a larger amount of burnable poisons. A number of burnable poison-containing fuel rods in adjacent with the large diameter water rod is increased in the second fuel assembly than the first fuel assembly. Then, the poison of the paired replacement fuel assemblies for the BWR type reactor can be annihilated simultaneously at the final stage of the cycle. Accordingly, fuels for a BWR type reactor excellent in economical property and safety and facilitating the design of the replacement reactor core can be obtained. (N.H.)

NABUB a non-saturated model of coolant boiling in a fast reactor sub-assembly

International Nuclear Information System (INIS)

Brook, A.J.; Mills, D.S.

1975-08-01

A theoretical model is described of sodium boiling in a fast reactor sub-assembly in which the usual assumptions of a saturated vapour are not made. Instead, vapour pressure is calculated in a perfect gas basis, which enables some allowance to be made for the possible presence of non-condensables, which may inhibit the condensation f the vapour. Indications are given of the circumstances under which such inhibition might be expected to show the most marked effects, and some sample results ontained by the code are presented. These show that the coolant voiding pattern is most sensitive to restrictions on the condensing flux in the 100 to 200w/cm 2 range. If unrestricted condensation is assumed, the results of the code are in excellent agreement with more conventional saturation models. (author)

Acceptance of non-fuel assembly hardware by the Federal Waste Management System

International Nuclear Information System (INIS)

1990-03-01

This report is one of a series of eight prepared by E. R. Johnson Associates, Inc. (JAI) under ORNL's contract with DOE's OCRWM Systems Integration Program and in support of the Annual Capacity Report (ACR) Issue Resolution Process. The report topics relate specifically to the list of high-priority technical waste acceptance issues developed jointly by DOE and a utility-working group. JAI performed various analyses and studies on each topic to serve as starting points for further discussion and analysis leading eventually to finalizing the process by which DOE will accept spent fuel and waste into its waste management system. The eight reports are concerned with the conditions under which spent fuel and high-level waste will be accepted in the following categories: failed fuel; consolidated fuel and associated structural parts; non-fuel-assembly hardware; fuel in metal storage casks; fuel in multi-element sealed canisters; inspection and testing requirements for wastes; canister criteria; spent fuel selection for delivery; and defense and commercial high-level waste packages. 14 refs., 12 figs., 43 tabs

Micellar Self-Assembly of Block Copolymers for Fabrication of Nanostructured Membranes

KAUST Repository

Marques, Debora S.

2013-11-01

This research work examines the process of block copolymer membrane fabrication by self-assembly combined by non-solvent induced phase separation. Self-assembly takes place from the preparation of the primordial solution until the moment of immersion in a non-solvent bath. These mechanisms are driven thermodynamically but are limited by kinetic factors. It is shown in this work how the ordering of the assembly of micelles is improved by the solution parameters such as solvent quality and concentration of block copolymer. Order transitions are detected, yielding changes in the morphology. The evaporation of the solvents after casting is demonstrated to be essential to reach optimum membrane structure. The non-solvent bath stops the phase separation at an optimum evaporation time.

Non-uniform self-assembly : On the anisotropic architecture of α-synuclein supra-fibrillar aggregates

NARCIS (Netherlands)

Semerdzhiev, Slav A.; Shvadchak, Volodymyr V.; Subramaniam, Vinod; Claessens, Mireille M.A.E.

2017-01-01

Although the function of biopolymer hydrogels in nature depends on structural anisotropy at mesoscopic length scales, the self-assembly of such anisotropic structures in vitro is challenging. Here we show that fibrils of the protein α-synuclein spontaneously self-assemble into structurally

Assembly of primary cilia

DEFF Research Database (Denmark)

Pedersen, Lotte B; Veland, Iben R; Schrøder, Jacob M

2008-01-01

knowledge about IFT is based on studies performed in Chlamydomonas and Caenorhabditis elegans. Therefore, our review of the IFT literature includes studies performed in these two model organisms. The role of several non-IFT proteins (e.g., centrosomal proteins) in the ciliary assembly process is also...... discussed. Developmental Dynamics, 2008. (c) 2008 Wiley-Liss, Inc....

A spectrum correction method for fuel assembly rehomogenization

International Nuclear Information System (INIS)

Lee, Kyung Taek; Cho, Nam Zin

2004-01-01

To overcome the limitation of existing homogenization methods based on the single assembly calculation with zero current boundary condition, we propose a new rehomogenization method, named spectrum correction method (SCM), consisting of the multigroup energy spectrum approximation by spectrum correction and the condensed two-group heterogeneous single assembly calculations with non-zero current boundary condition. In SCM, the spectrum shifting phenomena caused by current across assembly interfaces are considered by the spectrum correction at group condensation stage at first. Then, heterogeneous single assembly calculations with two-group cross sections condensed by using corrected multigroup energy spectrum are performed to obtain rehomogenized nodal diffusion parameters, i.e., assembly-wise homogenized cross sections and discontinuity factors. To evaluate the performance of SCM, it was applied to the analytic function expansion nodal (AFEN) method and several test problems were solved. The results show that SCM can reduce the errors significantly both in multiplication factors and assembly averaged power distributions

Construction of Supramolecular Architectures via Self-assembly

Institute of Scientific and Technical Information of China (English)

Takeharu; Haino

2007-01-01

1 Results In this paper we report supramolecular polymeric nano networks formed by the molecular-recognition-directed self-assembly between a calix[5]arene and C60[1]. Covalently-linked double-calix[5]arenes take up C60 into their cavities[2]. This complementary interaction creates a strong non-covalent bonding; thus,the iterative self-assembly between dumbbell fullerene 1 and ditopic host 2 can produce the supramolecular polymer networks (See Fig.1).

Comparing de novo assemblers for 454 transcriptome data.

Science.gov (United States)

Kumar, Sujai; Blaxter, Mark L

2010-10-16

Roche 454 pyrosequencing has become a method of choice for generating transcriptome data from non-model organisms. Once the tens to hundreds of thousands of short (250-450 base) reads have been produced, it is important to correctly assemble these to estimate the sequence of all the transcripts. Most transcriptome assembly projects use only one program for assembling 454 pyrosequencing reads, but there is no evidence that the programs used to date are optimal. We have carried out a systematic comparison of five assemblers (CAP3, MIRA, Newbler, SeqMan and CLC) to establish best practices for transcriptome assemblies, using a new dataset from the parasitic nematode Litomosoides sigmodontis. Although no single assembler performed best on all our criteria, Newbler 2.5 gave longer contigs, better alignments to some reference sequences, and was fast and easy to use. SeqMan assemblies performed best on the criterion of recapitulating known transcripts, and had more novel sequence than the other assemblers, but generated an excess of small, redundant contigs. The remaining assemblers all performed almost as well, with the exception of Newbler 2.3 (the version currently used by most assembly projects), which generated assemblies that had significantly lower total length. As different assemblers use different underlying algorithms to generate contigs, we also explored merging of assemblies and found that the merged datasets not only aligned better to reference sequences than individual assemblies, but were also more consistent in the number and size of contigs. Transcriptome assemblies are smaller than genome assemblies and thus should be more computationally tractable, but are often harder because individual contigs can have highly variable read coverage. Comparing single assemblers, Newbler 2.5 performed best on our trial data set, but other assemblers were closely comparable. Combining differently optimal assemblies from different programs however gave a more credible

Toehold strand displacement-driven assembly of G-quadruplex DNA for enzyme-free and non-label sensitive fluorescent detection of thrombin.

Science.gov (United States)

Xu, Yunying; Zhou, Wenjiao; Zhou, Ming; Xiang, Yun; Yuan, Ruo; Chai, Yaqin

2015-02-15

Based on a new signal amplification strategy by the toehold strand displacement-driven cyclic assembly of G-quadruplex DNA, the development of an enzyme-free and non-label aptamer sensing approach for sensitive fluorescent detection of thrombin is described. The target thrombin associates with the corresponding aptamer of the partial dsDNA probes and liberates single stranded initiation sequences, which trigger the toehold strand displacement assembly of two G-quadruplex containing hairpin DNAs. This toehold strand displacement reaction leads to the cyclic reuse of the initiation sequences and the production of DNA assemblies with numerous G-quadruplex structures. The fluorescent dye, N-Methyl mesoporphyrin IX, binds to these G-quadruplex structures and generates significantly amplified fluorescent signals to achieve highly sensitive detection of thrombin down to 5 pM. Besides, this method shows high selectivity towards the target thrombin against other control proteins. The developed thrombin sensing method herein avoids the modification of the probes and the involvement of any enzyme or nanomaterial labels for signal amplification. With the successful demonstration for thrombin detection, our approach can be easily adopted to monitor other target molecules in a simple, low-cost, sensitive and selective way by choosing appropriate aptamer/ligand pairs. Copyright © 2014 Elsevier B.V. All rights reserved.

Nuclear fuel assembly top nozzle with improved arrangement of hold-down leaf spring assemblies

International Nuclear Information System (INIS)

De Mario, E.E.; Lawson, C.N.

1991-01-01

This patent describes a top nozzle for use in a fuel assembly having guide thimbles for mounting the top nozzle. It comprises: a lower adapter plate having a periphery bounding an interior thereof mountable to the guide thimbles: guide structures attached to and extending along the periphery of the adapter plate and upwardly therefrom; an upper hold-down plate mounted to the guide structures for slidable movement relative thereto such that the upper plate can move toward and away from the interior of the lower plate within the space bounded by the guide structures as the upper plate slidably moves along the guide structures; and leaf spring assemblies interposed between and engaged with the lower and upper plates so as to yieldably support the upper plate in spaced relation above the lower plate and bias the upper plate for movement away from the lower plate; the leaf spring assemblies being provided in a non-peripheral arrangement relative to the periphery of the lower plate in which the assemblies cross the interior of the lower plate in a diagonal fashion between adjacent ones of the guide structures

An assessment of the transportation costs of shipping non-fuel assembly hardware to FWMS facilities

International Nuclear Information System (INIS)

Shappert, L.B.; Joy, D.S.; Johnson, P.E.; Danese, F.L.; Best, R.E.

1991-01-01

This study examines the cost of using Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) Initiative I casks for transporting 62,700 MTU of spent fuel plus associated non-fuel assembly hardware (NFAH) between reactor sites and either a monitored retrievable storage (MRS) or a repository facility. The study further considers the benefits of increasing the cell size of the Initiative I BWR cask baskets to accommodate the fuel plus channels (which also would decrease the capacity of the cask to carry BWR fuel without channels) and the use of a commercial, non-spent-fuel cask to carry compacted NFAH that could not be shipped integrally. Costs that are developed involve transportation charges, capital costs for casks, and canning costs of NFAH that have been separated from the fuel. The results indicate that significant cost savings are possible if NFAH is accepted into the Federal Waste Management System (FWMS) that is either integral with the spent fuel, or consolidated if it has been separated. Shipment of unconsolidated NFAH is very expensive. Transportation costs for shipping to a western repository are approximately 50 to 75% higher than the costs for shipping to an eastern MRS

Optimizing de novo common wheat transcriptome assembly using short-read RNA-Seq data

Directory of Open Access Journals (Sweden)

Duan Jialei

2012-08-01

Full Text Available Abstract Background Rapid advances in next-generation sequencing methods have provided new opportunities for transcriptome sequencing (RNA-Seq. The unprecedented sequencing depth provided by RNA-Seq makes it a powerful and cost-efficient method for transcriptome study, and it has been widely used in model organisms and non-model organisms to identify and quantify RNA. For non-model organisms lacking well-defined genomes, de novo assembly is typically required for downstream RNA-Seq analyses, including SNP discovery and identification of genes differentially expressed by phenotypes. Although RNA-Seq has been successfully used to sequence many non-model organisms, the results of de novo assembly from short reads can still be improved by using recent bioinformatic developments. Results In this study, we used 212.6 million pair-end reads, which accounted for 16.2 Gb, to assemble the hexaploid wheat transcriptome. Two state-of-the-art assemblers, Trinity and Trans-ABySS, which use the single and multiple k-mer methods, respectively, were used, and the whole de novo assembly process was divided into the following four steps: pre-assembly, merging different samples, removal of redundancy and scaffolding. We documented every detail of these steps and how these steps influenced assembly performance to gain insight into transcriptome assembly from short reads. After optimization, the assembled transcripts were comparable to Sanger-derived ESTs in terms of both continuity and accuracy. We also provided considerable new wheat transcript data to the community. Conclusions It is feasible to assemble the hexaploid wheat transcriptome from short reads. Special attention should be paid to dealing with multiple samples to balance the spectrum of expression levels and redundancy. To obtain an accurate overview of RNA profiling, removal of redundancy may be crucial in de novo assembly.

Precision lens assembly with alignment turning system

Science.gov (United States)

Ho, Cheng-Fang; Huang, Chien-Yao; Lin, Yi-Hao; Kuo, Hui-Jean; Kuo, Ching-Hsiang; Hsu, Wei-Yao; Chen, Fong-Zhi

2017-10-01

The poker chip assembly with high precision lens barrels is widely applied to ultra-high performance optical system. ITRC applies the poker chip assembly technology to the high numerical aperture objective lenses and lithography projection lenses because of its high efficiency assembly process. In order to achieve high precision lens cell for poker chip assembly, an alignment turning system (ATS) is developed. The ATS includes measurement, alignment and turning modules. The measurement module is equipped with a non-contact displacement sensor (NCDS) and an autocollimator (ACM). The NCDS and ACM are used to measure centration errors of the top and the bottom surface of a lens respectively; then the amount of adjustment of displacement and tilt with respect to the rotational axis of the turning machine for the alignment module can be determined. After measurement, alignment and turning processes on the ATS, the centration error of a lens cell with 200 mm in diameter can be controlled within 10 arcsec. Furthermore, a poker chip assembly lens cell with three sub-cells is demonstrated, each sub-cells are measured and accomplished with alignment and turning processes. The lens assembly test for five times by each three technicians; the average transmission centration error of assembly lens is 12.45 arcsec. The results show that ATS can achieve high assembly efficiency for precision optical systems.

Bio-assembled, piezoelectric prawn shell made self-powered wearable sensor for non-invasive physiological signal monitoring

Science.gov (United States)

Ghosh, Sujoy Kumar; Mandal, Dipankar

2017-03-01

A human interactive self-powered wearable sensor is designed using waste by-product prawn shells. The structural origin of intrinsic piezoelectric characteristics of bio-assembled chitin nanofibers has been investigated. It allows the prawn shell to make a tactile sensor that performs also as a highly durable mechanical energy harvester/nanogenerator. The feasibility and fundamental physics of self-powered consumer electronics even from human perception is highlighted by prawn shells made nanogenerator (PSNG). High fidelity and non-invasive monitoring of vital signs, such as radial artery pulse wave and coughing actions, may lead to the potential use of PSNG for early intervention. It is presumed that PSNG has enormous future aspects in real-time as well as remote health care assessment.

Evaluating de Bruijn graph assemblers on 454 transcriptomic data.

Directory of Open Access Journals (Sweden)

Xianwen Ren

Full Text Available Next generation sequencing (NGS technologies have greatly changed the landscape of transcriptomic studies of non-model organisms. Since there is no reference genome available, de novo assembly methods play key roles in the analysis of these data sets. Because of the huge amount of data generated by NGS technologies for each run, many assemblers, e.g., ABySS, Velvet and Trinity, are developed based on a de Bruijn graph due to its time- and space-efficiency. However, most of these assemblers were developed initially for the Illumina/Solexa platform. The performance of these assemblers on 454 transcriptomic data is unknown. In this study, we evaluated and compared the relative performance of these de Bruijn graph based assemblers on both simulated and real 454 transcriptomic data. The results suggest that Trinity, the Illumina/Solexa-specialized transcriptomic assembler, performs the best among the multiple de Bruijn graph assemblers, comparable to or even outperforming the standard 454 assembler Newbler which is based on the overlap-layout-consensus algorithm. Our evaluation is expected to provide helpful guidance for researchers to choose assemblers when analyzing 454 transcriptomic data.

Nondestructive Assay Data Integration with the SKB-50 Assemblies - FY16 Update

International Nuclear Information System (INIS)

Tobin, Stephen Joseph; Fugate, Michael Lynn; Trellue, Holly Renee; DeBaere, Paul; Sjoland, Anders; Liljenfeldt, Henrik; Hu, Jianwei; Backstrom, Ulrika; Bengtsson, Martin; Burr, Tomas; Eliasson, Annika; Favalli, Andrea; Gauld, Ian; Grogan, Brandon; Jansson, Peter; Junell, Henrik; Schwalbach, Peter; Vaccaro, Stefano; Vo, Duc Ta; Wildestrand, Henrik

2016-01-01

A project to research the application of non-destructive assay (NDA) techniques for spent fuel assemblies is underway at the Central Interim Storage Facility for Spent Nuclear Fuel (for which the Swedish acronym is Clab) in Oskarshamn, Sweden. The research goals of this project contain both safeguards and non-safeguards interests. These nondestructive assay (NDA) technologies are designed to strengthen the technical toolkit of safeguard inspectors and others to determine the following technical goals more accurately; Verify initial enrichment, burnup, and cooling time of facility declaration for spent fuel assemblies; Detect replaced or missing pins from a given spent fuel assembly to confirm its integrity; and Estimate plutonium mass and related plutonium and uranium fissile mass parameters in spent fuel assemblies. Estimate heat content, and measure reactivity (multiplication).

Nondestructive Assay Data Integration with the SKB-50 Assemblies - FY16 Update

Energy Technology Data Exchange (ETDEWEB)

Tobin, Stephen Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fugate, Michael Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Trellue, Holly Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); DeBaere, Paul [DG Energy, Luxembourg (Germany); Sjoland, Anders [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Liljenfeldt, Henrik [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hu, Jianwei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Backstrom, Ulrika [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Vattenfall AB, Stockholm (Sweden); Bengtsson, Martin [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Vattenfall AB, Stockholm (Sweden); Burr, Tomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); International Atomic Energy Agency, Vienna (Austria); Eliasson, Annika [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Favalli, Andrea [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gauld, Ian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Grogan, Brandon [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jansson, Peter [Uppsala Univ. (Sweden); Junell, Henrik [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Schwalbach, Peter [DG Energy, Luxembourg (Germany); Vaccaro, Stefano [DG Energy, Luxembourg (Germany); Vo, Duc Ta [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wildestrand, Henrik [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Vattenfall AB, Stockholm (Sweden)

2016-10-28

A project to research the application of non-destructive assay (NDA) techniques for spent fuel assemblies is underway at the Central Interim Storage Facility for Spent Nuclear Fuel (for which the Swedish acronym is Clab) in Oskarshamn, Sweden. The research goals of this project contain both safeguards and non-safeguards interests. These nondestructive assay (NDA) technologies are designed to strengthen the technical toolkit of safeguard inspectors and others to determine the following technical goals more accurately; Verify initial enrichment, burnup, and cooling time of facility declaration for spent fuel assemblies; Detect replaced or missing pins from a given spent fuel assembly to confirm its integrity; and Estimate plutonium mass and related plutonium and uranium fissile mass parameters in spent fuel assemblies. Estimate heat content, and measure reactivity (multiplication).

Comparing de novo assemblers for 454 transcriptome data

Directory of Open Access Journals (Sweden)

Blaxter Mark L

2010-10-01

Full Text Available Abstract Background Roche 454 pyrosequencing has become a method of choice for generating transcriptome data from non-model organisms. Once the tens to hundreds of thousands of short (250-450 base reads have been produced, it is important to correctly assemble these to estimate the sequence of all the transcripts. Most transcriptome assembly projects use only one program for assembling 454 pyrosequencing reads, but there is no evidence that the programs used to date are optimal. We have carried out a systematic comparison of five assemblers (CAP3, MIRA, Newbler, SeqMan and CLC to establish best practices for transcriptome assemblies, using a new dataset from the parasitic nematode Litomosoides sigmodontis. Results Although no single assembler performed best on all our criteria, Newbler 2.5 gave longer contigs, better alignments to some reference sequences, and was fast and easy to use. SeqMan assemblies performed best on the criterion of recapitulating known transcripts, and had more novel sequence than the other assemblers, but generated an excess of small, redundant contigs. The remaining assemblers all performed almost as well, with the exception of Newbler 2.3 (the version currently used by most assembly projects, which generated assemblies that had significantly lower total length. As different assemblers use different underlying algorithms to generate contigs, we also explored merging of assemblies and found that the merged datasets not only aligned better to reference sequences than individual assemblies, but were also more consistent in the number and size of contigs. Conclusions Transcriptome assemblies are smaller than genome assemblies and thus should be more computationally tractable, but are often harder because individual contigs can have highly variable read coverage. Comparing single assemblers, Newbler 2.5 performed best on our trial data set, but other assemblers were closely comparable. Combining differently optimal assemblies

Self-assembled magnetic filter for highly efficient immunomagnetic separation.

Science.gov (United States)

Issadore, David; Shao, Huilin; Chung, Jaehoon; Newton, Andita; Pittet, Mikael; Weissleder, Ralph; Lee, Hakho

2011-01-07

We have developed a compact and inexpensive microfluidic chip, the self-assembled magnetic filter, to efficiently remove magnetically tagged cells from suspension. The self-assembled magnetic filter consists of a microfluidic channel built directly above a self-assembled NdFeB magnet. Micrometre-sized grains of NdFeB assemble to form alternating magnetic dipoles, creating a magnetic field with a very strong magnitude B (from the material) and field gradient ▽B (from the configuration) in the microfluidic channel. The magnetic force imparted on magnetic beads is measured to be comparable to state-of-the-art microfabricated magnets, allowing for efficient separations to be performed in a compact, simple device. The efficiency of the magnetic filter is characterized by sorting non-magnetic (polystyrene) beads from magnetic beads (iron oxide). The filter enriches the population of non-magnetic beads to magnetic beads by a factor of >10(5) with a recovery rate of 90% at 1 mL h(-1). The utility of the magnetic filter is demonstrated with a microfluidic device that sorts tumor cells from leukocytes using negative immunomagnetic selection, and concentrates the tumor cells on an integrated membrane filter for optical detection.

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy.

Science.gov (United States)

Loquet, Antoine; Tolchard, James; Berbon, Melanie; Martinez, Denis; Habenstein, Birgit

2017-09-17

Supramolecular protein assemblies play fundamental roles in biological processes ranging from host-pathogen interaction, viral infection to the propagation of neurodegenerative disorders. Such assemblies consist in multiple protein subunits organized in a non-covalent way to form large macromolecular objects that can execute a variety of cellular functions or cause detrimental consequences. Atomic insights into the assembly mechanisms and the functioning of those macromolecular assemblies remain often scarce since their inherent insolubility and non-crystallinity often drastically reduces the quality of the data obtained from most techniques used in structural biology, such as X-ray crystallography and solution Nuclear Magnetic Resonance (NMR). We here present magic-angle spinning solid-state NMR spectroscopy (SSNMR) as a powerful method to investigate structures of macromolecular assemblies at atomic resolution. SSNMR can reveal atomic details on the assembled complex without size and solubility limitations. The protocol presented here describes the essential steps from the production of 13 C/ 15 N isotope-labeled macromolecular protein assemblies to the acquisition of standard SSNMR spectra and their analysis and interpretation. As an example, we show the pipeline of a SSNMR structural analysis of a filamentous protein assembly.

Mechanics of a crushable pebble assembly using discrete element method

International Nuclear Information System (INIS)

Annabattula, R.K.; Gan, Y.; Zhao, S.; Kamlah, M.

2012-01-01

The influence of crushing of individual pebbles on the overall strength of a pebble assembly is investigated using discrete element method. An assembly comprising of 5000 spherical pebbles is assigned with random critical failure energies with a Weibull distribution in accordance with the experimental observation. Then, the pebble assembly is subjected to uni-axial compression (ε 33 =1.5%) with periodic boundary conditions. The crushable pebble assembly shows a significant difference in stress–strain response in comparison to a non-crushable pebble assembly. The analysis shows that a ideal plasticity like behaviour (constant stress with increase in strain) is the characteristic of a crushable pebble assembly with sudden damage. The damage accumulation law plays a critical role in determining the critical stress while the critical number of completely failed pebbles at the onset of critical stress is independent of such a damage law. Furthermore, a loosely packed pebble assembly shows a higher crush resistance while the critical stress is insensitive to the packing factor (η) of the assembly.

Versatile, modular 3D microelectrode arrays for neuronal ensemble recordings: from design to fabrication, assembly, and functional validation in non-human primates

Science.gov (United States)

Barz, F.; Livi, A.; Lanzilotto, M.; Maranesi, M.; Bonini, L.; Paul, O.; Ruther, P.

2017-06-01

Objective. Application-specific designs of electrode arrays offer an improved effectiveness for providing access to targeted brain regions in neuroscientific research and brain machine interfaces. The simultaneous and stable recording of neuronal ensembles is the main goal in the design of advanced neural interfaces. Here, we describe the development and assembly of highly customizable 3D microelectrode arrays and demonstrate their recording performance in chronic applications in non-human primates. Approach. System assembly relies on a microfabricated stacking component that is combined with Michigan-style silicon-based electrode arrays interfacing highly flexible polyimide cables. Based on the novel stacking component, the lead time for implementing prototypes with altered electrode pitches is minimal. Once the fabrication and assembly accuracy of the stacked probes have been characterized, their recording performance is assessed during in vivo chronic experiments in awake rhesus macaques (Macaca mulatta) trained to execute reaching-grasping motor tasks. Main results. Using a single set of fabrication tools, we implemented three variants of the stacking component for electrode distances of 250, 300 and 350 µm in the stacking direction. We assembled neural probes with up to 96 channels and an electrode density of 98 electrodes mm-2. Furthermore, we demonstrate that the shank alignment is accurate to a few µm at an angular alignment better than 1°. Three 64-channel probes were chronically implanted in two monkeys providing single-unit activity on more than 60% of all channels and excellent recording stability. Histological tissue sections, obtained 52 d after implantation from one of the monkeys, showed minimal tissue damage, in accordance with the high quality and stability of the recorded neural activity. Significance. The versatility of our fabrication and assembly approach should significantly support the development of ideal interface geometries for a broad

FAMREC, PWR Lateral Mechanical Fuel Rod Assembly Response

International Nuclear Information System (INIS)

Guenzler, R.C.

1995-01-01

1 - Description of program or function: The Fuel Assembly Mechanical Response Code (FAMREC) calculates the lateral mechanical response of a row of fuel assemblies while allowing for two types of nonlinearities. The first type is a geometric nonlinearity in the form of gaps between individual assemblies and between peripheral assemblies and a boundary wall. Impacting is monitored across the gaps. The second nonlinearity is the permanent deformation of the fuel assembly spacer grid to compressive loading. 2 - Method of solution: The response is calculated in the modal plane. The coupled differential equations are solved in closed form using Laplace transformations. The discrete displacements and velocities are then calculated and the gaps in the system monitored at each axial elevation for impacting. These impact forces are then applied statistically at a given time-step, and equilibrium is found using a Gaussian elimination technique. Three impact force calculation methods are available: 1- a linear impact force and crushing load audit calculation, 2- a more detailed linear impact force and crushing load calculation, and 3- a non-linear grid calculation which allows for plastic deformation of the fuel assembly spacer grids. 3 - Restrictions on the complexity of the problem: Maxima of: 3601 time-steps and forces; 80 modes; 30 applied forces; 15 fuel assemblies; and 5 impact grids per assembly

Porcine transcriptome analysis based on 97 non-normalized cDNA libraries and assembly of 1,021,891 expressed sequence tags

DEFF Research Database (Denmark)

Gorodkin, Jan; Cirera, Susanna; Hedegaard, Jacob

2007-01-01

public databases. The Sino-Danish ESTs were generated from one normalized and 97 non-normalized cDNA libraries representing 35 different tissues and three developmental stages. RESULTS: Using the Distiller package, the ESTs were assembled to roughly 48,000 contigs and 73,000 singletons, of which...... with the greatest number of different expressed genes, whereas tissues with more specialized function, such as developing liver, have fewer expressed genes. There are at least 65 high confidence housekeeping gene candidates and 876 cDNA library-specific gene candidates. We identified differential expression...

Assembling consumption

DEFF Research Database (Denmark)

Assembling Consumption marks a definitive step in the institutionalisation of qualitative business research. By gathering leading scholars and educators who study markets, marketing and consumption through the lenses of philosophy, sociology and anthropology, this book clarifies and applies...... the investigative tools offered by assemblage theory, actor-network theory and non-representational theory. Clear theoretical explanation and methodological innovation, alongside empirical applications of these emerging frameworks will offer readers new and refreshing perspectives on consumer culture and market...... societies. This is an essential reading for both seasoned scholars and advanced students of markets, economies and social forms of consumption....

Feedbacks between community assembly and habitat selection shape variation in local colonization

Science.gov (United States)

Kraus, J.M.; Vonesh, J.R.

2010-01-01

1. Non-consumptive effects of predators are increasingly recognized as important drivers of community assembly and structure. Specifically, habitat selection responses to top predators during colonization and oviposition can lead to large differences in aquatic community structure, composition and diversity. 2. These differences among communities due to predators may develop as communities assemble, potentially altering the relative quality of predator vs. predator-free habitats through time. If so, community assembly would be expected to modify the subsequent behavioural responses of colonists to habitats containing top predators. Here, we test this hypothesis by manipulating community assembly and the presence of fish in experimental ponds and measuring their independent and combined effects on patterns of colonization by insects and amphibians. 3. Assembly modified habitat selection of dytscid beetles and hylid frogs by decreasing or even reversing avoidance of pools containing blue-spotted sunfish (Enneacanthus gloriosus). However, not all habitat selection responses to fish depended on assembly history. Hydrophilid beetles and mosquitoes avoided fish while chironomids were attracted to fish pools, regardless of assembly history. 4. Our results show that community assembly causes taxa-dependent feedbacks that can modify avoidance of habitats containing a top predator. Thus, non-consumptive effects of a top predator on community structure change as communities assemble and effects of competitors and other predators combine with the direct effects of top predators to shape colonization. 5. This work reinforces the importance of habitat selection for community assembly in aquatic systems, while illustrating the range of factors that may influence colonization rates and resulting community structure. Directly manipulating communities both during colonization and post-colonization is critical for elucidating how sequential processes interact to shape communities.

Spontaneous non-canonical assembly of CcmK hexameric components from β-carboxysome shells of cyanobacteria.

Directory of Open Access Journals (Sweden)

Luis F Garcia-Alles

Full Text Available CcmK proteins are major constituents of icosahedral shells of β-carboxysomes, a bacterial microcompartment that plays a key role for CO2 fixation in nature. Supported by the characterization of bidimensional (2D layers of packed CcmK hexamers in crystal and electron microscopy structures, CcmK are assumed to be the major components of icosahedral flat facets. Here, we reassessed the validity of this model by studying CcmK isoforms from Synechocystis sp. PCC6803. Native mass spectrometry studies confirmed that CcmK are hexamers in solution. Interestingly, potential pre-assembled intermediates were also detected with CcmK2. Atomic-force microscopy (AFM imaging under quasi-physiological conditions confirmed the formation of canonical flat sheets with CcmK4. Conversely, CcmK2 formed both canonical and striped-patterned patches, while CcmK1 assembled into remarkable supra-hexameric curved honeycomb-like mosaics. Mutational studies ascribed the propensity of CcmK1 to form round assemblies to a combination of two features shared by at least one CcmK isoform in most β-cyanobacteria: a displacement of an α helical portion towards the hexamer edge, where a potential phosphate binding funnel forms between packed hexamers, and the presence of a short C-terminal extension in CcmK1. All-atom molecular dynamics supported a contribution of phosphate molecules sandwiched between hexamers to bend CcmK1 assemblies. Formation of supra-hexameric curved structures could be reproduced in coarse-grained simulations, provided that adhesion forces to the support were weak. Apart from uncovering unprecedented CcmK self-assembly features, our data suggest the possibility that transitions between curved and flat assemblies, following cargo maturation, could be important for the biogenesis of β-carboxysomes, possibly also of other BMC.

Fuel assembly assessment from CVD image analysis: A feasibility study

International Nuclear Information System (INIS)

Lindsay, C.S.; Lindblad, T.

1997-05-01

The Swedish Nuclear Inspectorate commissioned a feasibility study of automatic assessment of fuel assemblies from images obtained with the digital Cerenkov viewing device currently in development. The goal is to assist the IAEA inspectors in evaluating the fuel since they typically have only a few seconds to inspect an assembly. We report results here in two main areas: Investigation of basic image processing and recognition techniques needed to enhance the images and find the assembly in the image; Study of the properties of the distributions of light from the assemblies to determine whether they provide unique signatures for different burn-up and cooling times for real fuel or indicate presence of non-fuel. 8 refs, 27 figs

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

Directory of Open Access Journals (Sweden)

Rose Franck

2007-01-01

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

Ebola virus VP35 blocks stress granule assembly.

Science.gov (United States)

Le Sage, Valerie; Cinti, Alessandro; McCarthy, Stephen; Amorim, Raquel; Rao, Shringar; Daino, Gian Luca; Tramontano, Enzo; Branch, Donald R; Mouland, Andrew J

2017-02-01

Stress granules (SGs) are dynamic cytoplasmic aggregates of translationally silenced mRNAs that assemble in response to environmental stress. SGs appear to play an important role in antiviral innate immunity and many viruses have evolved to block or subvert SGs components for their own benefit. Here, we demonstrate that intracellular Ebola virus (EBOV) replication and transcription-competent virus like particles (trVLP) infection does not lead to SG assembly but leads to a blockade to Arsenite-induced SG assembly. Moreover we show that EBOV VP35 represses the assembly of canonical and non-canonical SGs induced by a variety of pharmacological stresses. This SG blockade requires, at least in part, the C-terminal domain of VP35. Furthermore, results from our co-immunoprecipitation studies indicate that VP35 interacts with multiple SG components, including G3BP1, eIF3 and eEF2 through a stress- and RNA-independent mechanism. These data suggest a novel function for EBOV VP35 in the repression of SG assembly. Copyright © 2016 Elsevier Inc. All rights reserved.

Functional self-assembled lipidic systems derived from renewable resources.

Science.gov (United States)

Silverman, Julian R; Samateh, Malick; John, George

2016-01-01

Self-assembled lipidic amphiphile systems can create a variety of multi-functional soft materials with value-added properties. When employing natural reagents and following biocatalytic syntheses, self-assembling monomers may be inherently designed for degradation, making them potential alternatives to conventional and persistent polymers. By using non-covalent forces, self-assembled amphiphiles can form nanotubes, fibers, and other stimuli responsive architectures prime for further applied research and incorporation into commercial products. By viewing these lipid derivatives under a lens of green principles, there is the hope that in developing a structure-function relationship and functional smart materials that research may remain safe, economic, and efficient.

Mind the gap; seven reasons to close fragmented genome assemblies.

Science.gov (United States)

Thomma, Bart P H J; Seidl, Michael F; Shi-Kunne, Xiaoqian; Cook, David E; Bolton, Melvin D; van Kan, Jan A L; Faino, Luigi

2016-05-01

Like other domains of life, research into the biology of filamentous microbes has greatly benefited from the advent of whole-genome sequencing. Next-generation sequencing (NGS) technologies have revolutionized sequencing, making genomic sciences accessible to many academic laboratories including those that study non-model organisms. Thus, hundreds of fungal genomes have been sequenced and are publically available today, although these initiatives have typically yielded considerably fragmented genome assemblies that often lack large contiguous genomic regions. Many important genomic features are contained in intergenic DNA that is often missing in current genome assemblies, and recent studies underscore the significance of non-coding regions and repetitive elements for the life style, adaptability and evolution of many organisms. The study of particular types of genetic elements, such as telomeres, centromeres, repetitive elements, effectors, and clusters of co-regulated genes, but also of phenomena such as structural rearrangements, genome compartmentalization and epigenetics, greatly benefits from having a contiguous and high-quality, preferably even complete and gapless, genome assembly. Here we discuss a number of important reasons to produce gapless, finished, genome assemblies to help answer important biological questions. Copyright © 2015 Elsevier Inc. All rights reserved.

Cucurbit[8]uril ternary complexes for biomolecular assemblies in solution and at interfaces

NARCIS (Netherlands)

Cavatorta, E.

2016-01-01

Self-assembly allows for rationally designed molecular platforms that exploit specific, directional, tunable and reversible non-covalent interactions. The dynamic nature of such supramolecular interactions gives rise to self-assembled systems that can sense and respond to physiological cues, or that

Robotically Assembled Aerospace Structures: Digital Material Assembly using a Gantry-Type Assembler

Science.gov (United States)

Trinh, Greenfield; Copplestone, Grace; O'Connor, Molly; Hu, Steven; Nowak, Sebastian; Cheung, Kenneth; Jenett, Benjamin; Cellucci, Daniel

2017-01-01

This paper evaluates the development of automated assembly techniques for discrete lattice structures using a multi-axis gantry type CNC machine. These lattices are made of discrete components called "digital materials." We present the development of a specialized end effector that works in conjunction with the CNC machine to assemble these lattices. With this configuration we are able to place voxels at a rate of 1.5 per minute. The scalability of digital material structures due to the incremental modular assembly is one of its key traits and an important metric of interest. We investigate the build times of a 5x5 beam structure on the scale of 1 meter (325 parts), 10 meters (3,250 parts), and 30 meters (9,750 parts). Utilizing the current configuration with a single end effector, performing serial assembly with a globally fixed feed station at the edge of the build volume, the build time increases according to a scaling law of n4, where n is the build scale. Build times can be reduced significantly by integrating feed systems into the gantry itself, resulting in a scaling law of n3. A completely serial assembly process will encounter time limitations as build scale increases. Automated assembly for digital materials can assemble high performance structures from discrete parts, and techniques such as built in feed systems, parallelization, and optimization of the fastening process will yield much higher throughput.

Sequence assembly

DEFF Research Database (Denmark)

Scheibye-Alsing, Karsten; Hoffmann, S.; Frankel, Annett Maria

2009-01-01

Despite the rapidly increasing number of sequenced and re-sequenced genomes, many issues regarding the computational assembly of large-scale sequencing data have remain unresolved. Computational assembly is crucial in large genome projects as well for the evolving high-throughput technologies and...... in genomic DNA, highly expressed genes and alternative transcripts in EST sequences. We summarize existing comparisons of different assemblers and provide a detailed descriptions and directions for download of assembly programs at: http://genome.ku.dk/resources/assembly/methods.html....

Chitosan Based Self-Assembled Nanoparticles in Drug Delivery

Directory of Open Access Journals (Sweden)

Javier Pérez Quiñones

2018-02-01

Full Text Available Chitosan is a cationic polysaccharide that is usually obtained by alkaline deacetylation of chitin poly(N-acetylglucosamine. It is biocompatible, biodegradable, mucoadhesive, and non-toxic. These excellent biological properties make chitosan a good candidate for a platform in developing drug delivery systems having improved biodistribution, increased specificity and sensitivity, and reduced pharmacological toxicity. In particular, chitosan nanoparticles are found to be appropriate for non-invasive routes of drug administration: oral, nasal, pulmonary and ocular routes. These applications are facilitated by the absorption-enhancing effect of chitosan. Many procedures for obtaining chitosan nanoparticles have been proposed. Particularly, the introduction of hydrophobic moieties into chitosan molecules by grafting to generate a hydrophobic-hydrophilic balance promoting self-assembly is a current and appealing approach. The grafting agent can be a hydrophobic moiety forming micelles that can entrap lipophilic drugs or it can be the drug itself. Another suitable way to generate self-assembled chitosan nanoparticles is through the formation of polyelectrolyte complexes with polyanions. This paper reviews the main approaches for preparing chitosan nanoparticles by self-assembly through both procedures, and illustrates the state of the art of their application in drug delivery.

IWR-solution for the ITER vacuum vessel assembly

Energy Technology Data Exchange (ETDEWEB)

Wu, H., E-mail: huapeng@lut.fi [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Handroos, H. [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Pela, P. [Tekes (Finland); Wang, Y. [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland)

2011-10-15

The assembly of ITER vacuum vessel (VV) is still a very big challenge as the process can only be done from inside the VV. The welding of the VV assembly is carried out using the dedicated robotic systems. The main functions of the robots are: (i) measuring the actual space between every two sectors, (ii) positioning of the 150 kg splice plates between the sector shells, (iii) welding the splice plates to the sector shells, (iv) NDT of the welds, (v) repairing, including machining of the welds, (vi) He-leak tests of the welds, and (vii) the non-planned functions that may turn out. This paper presents a reasonable method to assemble the ITER VV. In this article, one parallel mobile robot, running on the track rail fixed on the wall inside the VV, is designed and tested. The assembling process, carried out by the mobile robot together with the welding robot, is presented.

Bacteriophage Assembly

Directory of Open Access Journals (Sweden)

Anastasia A. Aksyuk

2011-02-01

Full Text Available Bacteriophages have been a model system to study assembly processes for over half a century. Formation of infectious phage particles involves specific protein-protein and protein-nucleic acid interactions, as well as large conformational changes of assembly precursors. The sequence and molecular mechanisms of phage assembly have been elucidated by a variety of methods. Differences and similarities of assembly processes in several different groups of bacteriophages are discussed in this review. The general principles of phage assembly are applicable to many macromolecular complexes.

Structural integrity assessment and stress measurement of CHASNUPP-1 fuel assembly

Directory of Open Access Journals (Sweden)

Waseem

2016-01-01

Full Text Available Fuel assembly of the PWR nuclear power plant is a long and flexible structure. This study has been made in an attempt to find the structural integrity of the fuel assembly (FA of Chashma Nuclear Power Plant-1 (CHASNUPP-1 at room temperature in air. The non-linear contact and structural tensile analysis have been performed using ANSYS 13.0, in order to determine the fuel assembly (FA elongation behaviour as well as the location and values of the stress intensity and stresses developed in axial direction under applied tensile load of 9800 N or 2 g being the fuel assembly handling or lifting load [Y. Zhang et al., Fuel assembly design report, SNERDI, China, 1994]. The finite element (FE model comprises spacer grids, fuel rods, flexible contacts between the fuel rods and grid's supports system and guide thimbles with dash-pots and flow holes, in addition to the spot welds between spacer grids and guide thimbles, has been developed using Shell181, Conta174 and Targe170 elements. FA is a non-straight structure. The actual behavior of the geometry is non-linear due to its curvature or design tolerance. It has been observed that fuel assembly elongation values obtained through FE analysis and experiment [SNERDI Tech. Doc., Mechanical strength and calculation for fuel assembly, Technical Report, F3.2.1, China, 1994] under applied tensile load are comparable and show approximately linear behaviors. Therefore, it seems that the permanent elongation of fuel assembly may not occur at the specified load. Moreover, the values of stresses obtained at different locations of the fuel assembly are also comparable with the stress values of the experiment determined at the same locations through strain gauges. Since the results of both studies (analytical and experimental are comparable, therefore, validation of the FE methodology is confirmed. The stress intensity of the FE model and maximum stresses developed along the guide thimbles in axial direction are

MYBPH inhibits NM IIA assembly via direct interaction with NMHC IIA and reduces cell motility

International Nuclear Information System (INIS)

Hosono, Yasuyuki; Usukura, Jiro; Yamaguchi, Tomoya; Yanagisawa, Kiyoshi; Suzuki, Motoshi; Takahashi, Takashi

2012-01-01

Highlights: ► MYBPH inhibits NMHC IIA assembly and cell motility. ► MYBPH interacts to assembly-competent NM IIA. ► MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA. -- Abstract: Actomyosin filament assembly is a critical step in tumor cell migration. We previously found that myosin binding protein H (MYBPH) is directly transactivated by the TTF-1 lineage-survival oncogene in lung adenocarcinomas and inhibits phosphorylation of the myosin regulatory light chain (RLC) of non-muscle myosin IIA (NM IIA) via direct interaction with Rho kinase 1 (ROCK1). Here, we report that MYBPH also directly interacts with an additional molecule, non-muscle myosin heavy chain IIA (NMHC IIA), which was found to occur between MYBPH and the rod portion of NMHC IIA. MYBPH inhibited NMHC IIA assembly and reduced cell motility. Conversely, siMYBPH-induced increased motility was partially, yet significantly, suppressed by blebbistatin, a non-muscle myosin II inhibitor, while more profound effects were attained by combined treatment with siROCK1 and blebbistatin. Electron microscopy observations showed well-ordered paracrystals of NMHC IIA reflecting an assembled state, which were significantly less frequently observed in the presence of MYBPH. Furthermore, an in vitro sedimentation assay showed that a greater amount of NMHC IIA was in an unassembled state in the presence of MYBPH. Interestingly, treatment with a ROCK inhibitor that impairs transition of NM IIA from an assembly-incompetent to assembly-competent state reduced the interaction between MYBPH and NMHC IIA, suggesting that MYBPH has higher affinity to assembly-competent NM IIA. These results suggest that MYBPH inhibits RLC and NMHC IIA, independent components of NM IIA, and negatively regulates actomyosin organization at 2 distinct steps, resulting in firm inhibition of NM IIA assembly.

A structurally diverse library of safe-by-design citrem-phospholipid lamellar and non-lamellar liquid crystalline nano-assemblies

DEFF Research Database (Denmark)

Mat Azmi, Intan Diana Binti; Wibroe, Peter Popp; Wu, Lin-Ping

2016-01-01

). This engineered library is structurally stable in human plasma as well as being hemocompatible (non-hemolytic, and poor activator of the complement system). By varying citrem to lipid weight ratio, the nanodispersion susceptibility to macrophage uptake could also be modulated. Finally, the formation...... their applications in intravenous drug delivery and targeting. Using a binary mixture of citrem and soy phosphatidylcholine (SPC) at different weight ratios, we describe a library of colloidally stable aqueous and hemocompatible nanodispersions of diverse nanoarchitectures (internal self-assembled nanostructures...... of nanodispersions comprising internally V2 (inverse bicontinuous cubic) and H2 (inverse hexagonal) nanoarchitectures was achieved without the use of an organic solvent, a secondary emulsifier, or high-energy input. The tunable binary citrem/SPC nanoplatform holds promise for future development of hemocompatible...

Optimizing Transcriptome Assemblies for Eleusine indica Leaf and Seedling by Combining Multiple Assemblies from Three De Novo Assemblers

Directory of Open Access Journals (Sweden)

Shu Chen

2015-03-01

Full Text Available Due to rapid advances in sequencing technology, increasing amounts of genomic and transcriptomic data are available for plant species, presenting enormous challenges for biocomputing analysis. A crucial first step for a successful transcriptomics-based study is the building of a high-quality assembly. Here, we utilized three different de novo assemblers (Trinity, Velvet, and CLC and the EvidentialGene pipeline tr2aacds to assemble two optimized transcript sets for the notorious weed species, . Two RNA sequencing (RNA-seq datasets from leaf and aboveground seedlings were processed using three assemblers, which resulted in 20 assemblies for each dataset. The contig numbers and N50 values of each assembly were compared to study the effect of read number, k-mer size, and in silico normalization on assembly output. The 20 assemblies were then processed through the tr2aacds pipeline to remove redundant transcripts and to select the transcript set with the best coding potential. Each assembly contributed a considerable proportion to the final transcript combination with the exception of the CLC-k14. Thus each assembler and parameter set did assemble better contigs for certain transcripts. The redundancy, total contig number, N50, fully assembled contig number, and transcripts related to target-site herbicide resistance were evaluated for the EvidentialGene and Trinity assemblies. Comparing the EvidentialGene set with the Trinity assembly revealed improved quality and reduced redundancy in both leaf and seedling EvidentialGene sets. The optimized transcriptome references will be useful for studying herbicide resistance in and the evolutionary process in the three allotetraploid offspring.

Ecological assembly rules in plant communities--approaches, patterns and prospects.

Science.gov (United States)

Götzenberger, Lars; de Bello, Francesco; Bråthen, Kari Anne; Davison, John; Dubuis, Anne; Guisan, Antoine; Lepš, Jan; Lindborg, Regina; Moora, Mari; Pärtel, Meelis; Pellissier, Loic; Pottier, Julien; Vittoz, Pascal; Zobel, Kristjan; Zobel, Martin

2012-02-01

Understanding how communities of living organisms assemble has been a central question in ecology since the early days of the discipline. Disentangling the different processes involved in community assembly is not only interesting in itself but also crucial for an understanding of how communities will behave under future environmental scenarios. The traditional concept of assembly rules reflects the notion that species do not co-occur randomly but are restricted in their co-occurrence by interspecific competition. This concept can be redefined in a more general framework where the co-occurrence of species is a product of chance, historical patterns of speciation and migration, dispersal, abiotic environmental factors, and biotic interactions, with none of these processes being mutually exclusive. Here we present a survey and meta-analyses of 59 papers that compare observed patterns in plant communities with null models simulating random patterns of species assembly. According to the type of data under study and the different methods that are applied to detect community assembly, we distinguish four main types of approach in the published literature: species co-occurrence, niche limitation, guild proportionality and limiting similarity. Results from our meta-analyses suggest that non-random co-occurrence of plant species is not a widespread phenomenon. However, whether this finding reflects the individualistic nature of plant communities or is caused by methodological shortcomings associated with the studies considered cannot be discerned from the available metadata. We advocate that more thorough surveys be conducted using a set of standardized methods to test for the existence of assembly rules in data sets spanning larger biological and geographical scales than have been considered until now. We underpin this general advice with guidelines that should be considered in future assembly rules research. This will enable us to draw more accurate and general

Structural Basis of the pH-Dependent Assembly of a Botulinum Neurotoxin Complex

OpenAIRE

Matsui, Tsutomu; Gu, Shenyan; Lam, Kwok-ho; Carter, Lester G.; Rummel, Andreas; Mathews, Irimpan I.; Jin, Rongsheng

2014-01-01

Botulinum neurotoxins (BoNTs) are among the most poisonous biological substances known. They assemble with non-toxic non-hemagglutinin (NTNHA) protein to form the minimally functional progenitor toxin complexes (M-PTC), which protects BoNT in the gastrointestinal tract and release it upon entry into the circulation. Here we provide molecular insight into the assembly between BoNT/A and NTNHA-A using small-angle X-ray scattering. We found that the free form BoNT/A maintains a pH-independent co...

Dynamic DNA devices and assemblies formed by shape-complementary, non-base pairing 3D components

Science.gov (United States)

Gerling, Thomas; Wagenbauer, Klaus F.; Neuner, Andrea M.; Dietz, Hendrik

2015-03-01

We demonstrate that discrete three-dimensional (3D) DNA components can specifically self-assemble in solution on the basis of shape-complementarity and without base pairing. Using this principle, we produced homo- and heteromultimeric objects, including micrometer-scale one- and two-stranded filaments and lattices, as well as reconfigurable devices, including an actuator, a switchable gear, an unfoldable nanobook, and a nanorobot. These multidomain assemblies were stabilized via short-ranged nucleobase stacking bonds that compete against electrostatic repulsion between the components’ interfaces. Using imaging by electron microscopy, ensemble and single-molecule fluorescence resonance energy transfer spectroscopy, and electrophoretic mobility analysis, we show that the balance between attractive and repulsive interactions, and thus the conformation of the assemblies, may be finely controlled by global parameters such as cation concentration or temperature and by an allosteric mechanism based on strand-displacement reactions.

RISC assembly: Coordination between small RNAs and Argonaute proteins.

Science.gov (United States)

Kobayashi, Hotaka; Tomari, Yukihide

2016-01-01

Non-coding RNAs generally form ribonucleoprotein (RNP) complexes with their partner proteins to exert their functions. Small RNAs, including microRNAs, small interfering RNAs, and PIWI-interacting RNAs, assemble with Argonaute (Ago) family proteins into the effector complex called RNA-induced silencing complex (RISC), which mediates sequence-specific target gene silencing. RISC assembly is not a simple binding between a small RNA and Ago; rather, it follows an ordered multi-step pathway that requires specific accessory factors. Some steps of RISC assembly and RISC-mediated gene silencing are dependent on or facilitated by particular intracellular platforms, suggesting their spatial regulation. In this review, we summarize the currently known mechanisms for RISC assembly of each small RNA class and propose a revised model for the role of the chaperone machinery in the duplex-initiated RISC assembly pathway. This article is part of a Special Issue entitled: Clues to long noncoding RNA taxonomy1, edited by Dr. Tetsuro Hirose and Dr. Shinichi Nakagawa. Copyright © 2015 Elsevier B.V. All rights reserved.

Generic concept to program the time domain of self-assemblies with a self-regulation mechanism.

Science.gov (United States)

Heuser, Thomas; Steppert, Ann-Kathrin; Lopez, Catalina Molano; Zhu, Baolei; Walther, Andreas

2015-04-08

Nature regulates complex structures in space and time via feedback loops, kinetically controlled transformations, and under energy dissipation to allow non-equilibrium processes. Although man-made static self-assemblies realize excellent control over hierarchical structures via molecular programming, managing their temporal destiny by self-regulation is a largely unsolved challenge. Herein, we introduce a generic concept to control the time domain by programming the lifetimes of switchable self-assemblies in closed systems. We conceive dormant deactivators that, in combination with fast promoters, enable a unique kinetic balance to establish an autonomously self-regulating, transient pH-state, whose duration can be programmed over orders of magnitude-from minutes to days. Coupling this non-equilibrium state to pH-switchable self-assemblies allows predicting their assembly/disassembly fate in time, similar to a precise self-destruction mechanism. We demonstrate a platform approach by programming self-assembly lifetimes of block copolymers, nanoparticles, and peptides, enabling dynamic materials with a self-regulation functionality.

Fuel assemblies

International Nuclear Information System (INIS)

Nakatsuka, Masafumi.

1979-01-01

Purpose: To prevent scattering of gaseous fission products released from fuel assemblies stored in an fbr type reactor. Constitution; A cap provided with means capable of storing gas is adapted to amount to the assembly handling head, for example, by way of threading in a storage rack of spent fuel assemblies consisting of a bottom plate, a top plate and an assembly support mechanism. By previously eliminating the gas inside of the assembly and the cap in the storage rack, gaseous fission products upon loading, if released from fuel rods during storage, are stored in the cap and do not scatter in the storage rack. (Horiuchi, T.)

Transcriptator: An Automated Computational Pipeline to Annotate Assembled Reads and Identify Non Coding RNA.

Directory of Open Access Journals (Sweden)

Kumar Parijat Tripathi

Full Text Available RNA-seq is a new tool to measure RNA transcript counts, using high-throughput sequencing at an extraordinary accuracy. It provides quantitative means to explore the transcriptome of an organism of interest. However, interpreting this extremely large data into biological knowledge is a problem, and biologist-friendly tools are lacking. In our lab, we developed Transcriptator, a web application based on a computational Python pipeline with a user-friendly Java interface. This pipeline uses the web services available for BLAST (Basis Local Search Alignment Tool, QuickGO and DAVID (Database for Annotation, Visualization and Integrated Discovery tools. It offers a report on statistical analysis of functional and Gene Ontology (GO annotation's enrichment. It helps users to identify enriched biological themes, particularly GO terms, pathways, domains, gene/proteins features and protein-protein interactions related informations. It clusters the transcripts based on functional annotations and generates a tabular report for functional and gene ontology annotations for each submitted transcript to the web server. The implementation of QuickGo web-services in our pipeline enable the users to carry out GO-Slim analysis, whereas the integration of PORTRAIT (Prediction of transcriptomic non coding RNA (ncRNA by ab initio methods helps to identify the non coding RNAs and their regulatory role in transcriptome. In summary, Transcriptator is a useful software for both NGS and array data. It helps the users to characterize the de-novo assembled reads, obtained from NGS experiments for non-referenced organisms, while it also performs the functional enrichment analysis of differentially expressed transcripts/genes for both RNA-seq and micro-array experiments. It generates easy to read tables and interactive charts for better understanding of the data. The pipeline is modular in nature, and provides an opportunity to add new plugins in the future. Web application is

Construction and actuation of a microscopic gear assembly formed using optical tweezers

International Nuclear Information System (INIS)

Kim, Jung-Dae; Lee, Yong-Gu

2013-01-01

The assembly of micrometer-sized parts is an important manufacturing process; any development in it could potentially change the current manufacturing practices for micrometer-scale devices. Due to the lack of reliable microassembly techniques, these devices are often manufactured using silicon, which includes etching and depositions with little use of assembly processes. The result is the requirement of specialized manufacturing conditions with hazardous byproducts and limited applications where only simple mechanisms are allowed. Optical tweezers are non-contact type manipulators that are very suitable for assembling microparts and solve one of the most difficult problems for microassembly, which is the sticking of the physical manipulator to the micropart. Although contact type manipulators can be surface modified to be non-sticky, this involves extra preprocessing—optical tweezers do not require such additional efforts. The weakness of using optical tweezers is that the permanent assembly of parts is not possible as only very small forces can be applied. We introduce an advanced microassembly environment with the combined use of optical tweezers and a motorized microtip, where the former is used to position two parts and the latter is used to introduce deformation in the parts so that they form a strongly fitted assembly. (paper)

Exciplex fluorescence emission from simple organic intramolecular constructs in non-polar and highly polar media as model systems for DNA-assembled exciplex detectors.

Science.gov (United States)

Bichenkova, Elena V; Sardarian, Ali R; Wilton, Amanda N; Bonnet, Pascal; Bryce, Richard A; Douglas, Kenneth T

2006-01-21

Organic intramolecular exciplexes, N-(4-dimethylaminobenzyl)-N-(1-pyrenemethyl)amine (1) and N'-4-dimethylaminonaphthyl-N-(1-pyrenemethyl)amine (2), were used as model systems to reveal major factors affecting their exciplex fluorescence, and thus lay the basis for developing emissive target-assembled exciplexes for DNA-mounted systems in solution. These models with an aromatic pyrenyl hydrocarbon moiety as an electron acceptor appropriately connected to an aromatic dimethylamino electron donor component (N,N-dimethylaminophenyl or N,N-dimethylaminonaphthyl) showed strong intramolecular exciplex emission in both non-polar and highly polar solvents. The effect of dielectric constant on the maximum wavelength for exciplex emission was studied, and emission was observed for 1 and 2 over the full range of solvent from non-polar hydrocarbons up to N-methylformamide with a dielectric constant of 182. Quantum yields were determined for these intramolecular exciplexes in a range of solvents relative to that for Hoechst 33,258. Conformational analysis of 1 was performed both computationally and via qualitative 2D NMR using (1)H-NOESY experiments. The results obtained indicated the contribution of pre-folded conformation(s) to the ground state of 1 conducive to exciplex emission. This research provides the initial background for design of self-assembled, DNA-mounted exciplexes and underpins further development of exciplex-based hybridisation bioassays.

Viral capsid assembly as a model for protein aggregation diseases: Active processes catalyzed by cellular assembly machines comprising novel drug targets.

Science.gov (United States)

Marreiros, Rita; Müller-Schiffmann, Andreas; Bader, Verian; Selvarajah, Suganya; Dey, Debendranath; Lingappa, Vishwanath R; Korth, Carsten

2015-09-02

therapeutics. A key basis for the commonality between viral and neurodegenerative disease aggregation is a broader definition of assembly as more than just simple aggregation, particularly suited for the crowded cytoplasm. The assembly machines are collections of proteins that catalytically accelerate an assembly reaction that would occur spontaneously but too slowly to be relevant in vivo. Being an enzyme complex with a functional allosteric site, appropriated for a non-physiological purpose (e.g. viral infection or conformational disease), these assembly machines present a superior pharmacological target because inhibition of their active site will amplify an effect on their substrate reaction. Here, we present this hypothesis based on recent proof-of-principle studies against Aβ assembly relevant in Alzheimer's disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Electrodynamic tailoring of self-assembled three-dimensional electrospun constructs

Science.gov (United States)

Reis, Tiago C.; Correia, Ilídio J.; Aguiar-Ricardo, Ana

2013-07-01

The rational design of three-dimensional electrospun constructs (3DECs) can lead to striking topographies and tailored shapes of electrospun materials. This new generation of materials is suppressing some of the current limitations of the usual 2D non-woven electrospun fiber mats, such as small pore sizes or only flat shaped constructs. Herein, we pursued an explanation for the self-assembly of 3DECs based on electrodynamic simulations and experimental validation. We concluded that the self-assembly process is driven by the establishment of attractive electrostatic forces between the positively charged aerial fibers and the already collected ones, which tend to acquire a negatively charged network oriented towards the nozzle. The in situ polarization degree is strengthened by higher amounts of clustered fibers, and therefore the initial high density fibrous regions are the preliminary motifs for the self-assembly mechanism. As such regions increase their in situ polarization electrostatic repulsive forces will appear, favoring a competitive growth of these self-assembled fibrous clusters. Highly polarized regions will evidence higher distances between consecutive micro-assembled fibers (MAFs). Different processing parameters - deposition time, electric field intensity, concentration of polymer solution, environmental temperature and relative humidity - were evaluated in an attempt to control material's design.The rational design of three-dimensional electrospun constructs (3DECs) can lead to striking topographies and tailored shapes of electrospun materials. This new generation of materials is suppressing some of the current limitations of the usual 2D non-woven electrospun fiber mats, such as small pore sizes or only flat shaped constructs. Herein, we pursued an explanation for the self-assembly of 3DECs based on electrodynamic simulations and experimental validation. We concluded that the self-assembly process is driven by the establishment of attractive

Assembly of Liposomes Controlled by Triple Helix Formation

DEFF Research Database (Denmark)

Vogel, Stefan; Jakobsen, Ulla

2013-01-01

Attachment of DNA to the surface of different solid nanoparticles (e.g. gold- and silica nanoparticles) is well established and a number of DNA-modified solid nanoparticle systems have been applied to thermal denaturation analysis of oligonucleotides. We report herein the non-covalent immobilizat...... analysis (NTA) and dynamic light scattering (DLS) show independently from ultraviolet spectroscopy experiments the formation of liposome aggregates.......-covalent immobilization of oligonucleotides on the surface of soft nanoparticles (e.g. liposomes) and the subsequent controlled assembly by DNA triple helix formation. The non-covalent approach avoids tedious surface chemistry and necessary purification procedures and can simplify and extend the available methodology...... sequences (G or C-rich) to explore the applicability of the method for different triple helical assembly modes. We demonstrate advantages and limitations of the approach and proof the reversible and reproducible formation of liposome aggregates during thermal denaturation cycles. Nanoparticle tracking...

Functional redundancy patterns reveal non-random assembly rules in a species-rich marine assemblage.

Directory of Open Access Journals (Sweden)

Nicolas Guillemot

Full Text Available The relationship between species and the functional diversity of assemblages is fundamental in ecology because it contains key information on functional redundancy, and functionally redundant ecosystems are thought to be more resilient, resistant and stable. However, this relationship is poorly understood and undocumented for species-rich coastal marine ecosystems. Here, we used underwater visual censuses to examine the patterns of functional redundancy for one of the most diverse vertebrate assemblages, the coral reef fishes of New Caledonia, South Pacific. First, we found that the relationship between functional and species diversity displayed a non-asymptotic power-shaped curve, implying that rare functions and species mainly occur in highly diverse assemblages. Second, we showed that the distribution of species amongst possible functions was significantly different from a random distribution up to a threshold of ∼90 species/transect. Redundancy patterns for each function further revealed that some functions displayed fast rates of increase in redundancy at low species diversity, whereas others were only becoming redundant past a certain threshold. This suggested non-random assembly rules and the existence of some primordial functions that would need to be fulfilled in priority so that coral reef fish assemblages can gain a basic ecological structure. Last, we found little effect of habitat on the shape of the functional-species diversity relationship and on the redundancy of functions, although habitat is known to largely determine assemblage characteristics such as species composition, biomass, and abundance. Our study shows that low functional redundancy is characteristic of this highly diverse fish assemblage, and, therefore, that even species-rich ecosystems such as coral reefs may be vulnerable to the removal of a few keystone species.

INSURANCE OF KNITTED PRODUCTS QUALITY THROUGH THE ANALYSIS AND EVALUATION OF NON-QUALITY DURING ASSEMBLY BY STITCHING

Directory of Open Access Journals (Sweden)

LUTIC Liliana

2014-05-01

Full Text Available In a knitting factory, any activity oriented toward evaluation, maintenance or improvement of products quality level is based on measuring and examining the product quality characteristics, in order to establish conformity to the quality specifications and/or naming the non-quality characteristics, thus noticing defects or fabrication deficiencies. The quality of the stitching operation has a particular influence on the finite product quality and is determined on side by the quality of knitted pieces, and on the other by insuring the correlation between the technological parameters of the stitching operation and the physico-mechanical characteristics of the knittings that are to be assembled through stitching. Although the product execution processes comprise of manufacturing the elements and distinct subassemblies and their ulterior assembly, they present various difference dictated by the constructive particularities of the machine, as well as fabric characteristics. Because of the multiple interactions between the material, yarn and working parts of the sawing machine, inadequacies in the technological discipline can result in negative effects on both the knitted and stitching thread as well as the machine. A part of these can be fixed by extra time consuming tasks (yarn breaks, stitching ruffling etc., while other defects appear during the usage of the product cheapening it (stitch tearing by perforating the knitted on the stitching line, pilling effect, dimensional instability etc.. This paper systematically presents, the main defects that may occur during the stitching operation of the products made out of circular knitted, as well as the causes that generate them along with preventive or corrective actions.

Self-assembly via anisotropic interactions : Modeling association kinetics of patchy particle systems and self-assembly induced by critical Casimir forces

NARCIS (Netherlands)

Newton, A.C.

2017-01-01

Self-assembly, the non-dissipative spontaneous formation of structural order spans many length scales, from amphiphilic molecules forming micelles to stars forming galaxies. This thesis mainly deals with systems on the colloidal length scale where the size of a particle is between a nanometer and a

ABB. CASE's GUARDIANTM Debris Resistant Fuel Assembly Design

International Nuclear Information System (INIS)

Dixon, D. J.; Wohlsen, W. D.

1992-01-01

ABB CE's experience, that 72% of all recent fuel-rod failures are caused by debris fretting, is typical. In response to this problem, ABB Combustion Engineering began supplying in the late 1980s fuel assemblies with a variety of debris resistant features, including both long-end caps and small flow holes. Now ABB CAE has developed an advanced debris resistant design concept, GUARDIAN TM , which has the advantage of capturing and retaining more debris than other designs, while displacing less plenum or active fuel volume than the long end-cap design. GUARDIAN TM design features have now been implemented into four different assembly designs. ABB CASE's GUARDIAN TM fuel assembly is an advanced debris-resistant design which has both superior filtering performance and uniquely, excellent debris retention, Retention effectively removes the debris from circulation in the coolant so that it is not able to threaten the fuel again. GUARDIAN TM features have been incorporated into four ABB. CAE fuel assembly designs. These assemblies are all fully compatible with the NSLS, and full-batch operation with GUARDIAN TM began in 1992. The number of plants of both CAE and non-CAE design which accept GUARDIAN TM for debris protection is expected to grow significantly during the next few years

Sensor mount assemblies and sensor assemblies

Science.gov (United States)

Miller, David H [Redondo Beach, CA

2012-04-10

Sensor mount assemblies and sensor assemblies are provided. In an embodiment, by way of example only, a sensor mount assembly includes a busbar, a main body, a backing surface, and a first finger. The busbar has a first end and a second end. The main body is overmolded onto the busbar. The backing surface extends radially outwardly relative to the main body. The first finger extends axially from the backing surface, and the first finger has a first end, a second end, and a tooth. The first end of the first finger is disposed on the backing surface, and the tooth is formed on the second end of the first finger.

Liaison concatenation – A method to obtain feasible assembly ...

Indian Academy of Sciences (India)

non-possible assembly sequences using liaison graph. In this paper a new ... Applications (CATIA) software is a user friendly CAD tool with the feasibility of .... to perform the contact analysis to check the possibility of interference. Table 5.

Modification of the ANC Nodal Code for analysis of PWR assembly bow

International Nuclear Information System (INIS)

Franceschini, Fausto; Fetterman, Robert J.; Little, David C.

2008-01-01

Refueling operations at certain PWR cores have revealed fuel assemblies with assembly bow that was higher than expected. As the fuel assemblies bow, the gaps between assemblies change from the uniform nominal configuration. This causes a change in the water volume which affects neutron moderation and thereby power distribution, fuel depletion history, rod internal pressure, etc., with non-trivial impacts on the safety analysis. Westinghouse has developed a new methodology for incorporation of assembly bow in its reload safety analysis package. As part of the new process, the standard Westinghouse reactor physics tool for core analysis, the Advanced Nodal Code ANC, has been modified. The modified ANC, ANCGAP, enables explicit treatment of three-dimensional gap distributions in its neutronic calculations; its accuracy is similar to that of the standard ANC, as demonstrated through an extensive benchmark campaign conducted over a variety of fuel compositions and challenging gap configurations. These features make ANCGAP a crucial tool in the Westinghouse assembly bow package. (authors)

Modification of the ANC Nodal Code for analysis of PWR assembly bow

Energy Technology Data Exchange (ETDEWEB)

Franceschini, Fausto; Fetterman, Robert J.; Little, David C. [Westinghouse Electric Company LLC, Pittsburgh PA (United States)

2008-07-01

Refueling operations at certain PWR cores have revealed fuel assemblies with assembly bow that was higher than expected. As the fuel assemblies bow, the gaps between assemblies change from the uniform nominal configuration. This causes a change in the water volume which affects neutron moderation and thereby power distribution, fuel depletion history, rod internal pressure, etc., with non-trivial impacts on the safety analysis. Westinghouse has developed a new methodology for incorporation of assembly bow in its reload safety analysis package. As part of the new process, the standard Westinghouse reactor physics tool for core analysis, the Advanced Nodal Code ANC, has been modified. The modified ANC, ANCGAP, enables explicit treatment of three-dimensional gap distributions in its neutronic calculations; its accuracy is similar to that of the standard ANC, as demonstrated through an extensive benchmark campaign conducted over a variety of fuel compositions and challenging gap configurations. These features make ANCGAP a crucial tool in the Westinghouse assembly bow package. (authors)

Stabilization of Pt nanoparticles by single stranded DNA and the binary assembly of Au and Pt nanoparticles without hybridization

International Nuclear Information System (INIS)

Yang, J.; Lee, Jim Yang; Too, Heng-Phon; Chow, Gan-Moog; Gan, Leong M.

2006-01-01

The non-specific interaction between single stranded DNA (ssDNA) and 12 nm Pt nanoparticles is investigated in this work. The data show a strong and non-specific interaction between the two which can be exploited for the stabilization of Pt nanoparticles in aqueous solutions. Based on the experimental findings, a non-hybridization based protocol to assemble 17 nm Au and Pt nanoparticles (12 nm cubic and 3.6 nm spherical) by single-stranded DNA was developed. Transmission electron microscopy (TEM) and UV-visible spectroscopy confirmed that Au and Pt nanoparticles could be assembled by the non-specific interaction in an orderly manner. The experimental results also caution against the potential pitfalls in using DNA melting point analysis to infer metal nanoparticle assembly by DNA hybridization

The Self-Assembly of Nanogold for Optical Metamaterials

Science.gov (United States)

Nidetz, Robert A.

2011-12-01

Optical metamaterials are an emerging field that enables manipulation of light like never before. Producing optical metamaterials requires sub-wavelength building blocks. The focus here was to develop methods to produce building blocks for metamaterials from nanogold. Electron-beam lithography was used to define an aminosilane patterned chemical template in order to electrostatically self-assemble citrate-capped gold nanoparticles. Equilibrium self-assembly was achieved in 20 minutes by immersing chemical templates into gold nanoparticle solutions. The number of nanoparticles that self-assembled on an aminosilane dot was controlled by manipulating the diameters of the dots and nanoparticles. Adding salt to the nanoparticle solution enabled the nanoparticles to self-assemble in greater numbers on the same sized dot. However, the preparation of the nanoparticle solution containing salt was sensitive to spikes in the salt concentration which led to aggregation of the nanoparticles and non-specific deposition. Gold nanorods were also electrostatically self-assembled. Polyelectrolyte-coated gold nanorods were patterned with limited success. A polyelectrolyte chemical template also patterned gold nanorods, but the gold nanorods preferred to pattern on the edges of the pattern. Ligand-exchanged gold nanorods displayed the best self-assembly, but suffered from slow kinetics. Self-assembled gold nanoparticles were cross-linked with poly(diallyldimethylammonium chloride). The poly(diallyldimethylammonium chloride) allowed additional nanoparticles to pattern on top of the already patterned nanoparticles. Cross-linked nanoparticles were lifted-off of the substrate by sonication in a sodium hydroxide solution. The presence of van der Waals forces and/or amine bonding prevent the nanogold from lifting-off without sonication. A good-solvent evaporation process was used to self-assemble poly(styrene) coated gold nanoparticles into spherical microbead assemblies. The use of larger

Radiological characterization of spent control rod assemblies

International Nuclear Information System (INIS)

Lepel, E.A.; Robertson, D.E.; Thomas, C.W.; Pratt, S.L.; Haggard, D.L.

1995-10-01

This document represents the final report of an ongoing study to provide radiological characterizations, classifications, and assessments in support of the decommissioning of nuclear power stations. This report describes the results of non-destructive and laboratory radionuclide measurements, as well as waste classification assessments, of BWR and PWR spent control rod assemblies. The radionuclide inventories of these spent control rods were determined by three separate methodologies, including (1) direct assay techniques, (2) calculational techniques, and (3) by sampling and laboratory radiochemical analyses. For the BWR control rod blade (CRB) and PWR burnable poison rod assembly (BPRA), 60 Co and 63 Ni, present in the stainless steel cladding, were the most abundant neutron activation products. The most abundant radionuclide in the PWR rod cluster control assembly (RCCA) was 108m Ag (130 yr halflife) produced in the Ag-In-Cd alloy used as the neutron poison. This radionuclide will be the dominant contributor to the gamma dose rate for many hundreds of years. The results of the direct assay methods agree very well (±10%) with the sampling/radiochemical measurements. The results of the calculational methods agreed fairly well with the empirical measurements for the BPRA, but often varied by a factor of 5 to 10 for the CRB and the RCCA assemblies. If concentration averaging and encapsulation, as allowed by 10CFR61.55, is performed, then each of the entire control assemblies would be classified as Class C low-level radioactive waste

Refitting of the 'Celimene' hot cell for following up the fuel assembly of 900 MWe PWR power reactors

International Nuclear Information System (INIS)

Lhermenier, Andre; Van Craeynest, J.-C.

1980-05-01

The 'Celimene' cell adjoining the EL3 reactor provides for the acceptance, handling and the examination of irradiated fuel assemblies from power reactors (length approximately 4m, weight approximately 700 kg). Within the framework of the PWR fuel behavior follow-up or reprocessing, it is possible to extract an assembly representative of the normal fuel cycle, carry out non destructive tests on this assembly, extract pencils from it and re-insert this assembly, after refitting the head, into the normal fuel cycle for handling in a reprocessing plant or storage pond. Given suitable refitting techniques, the re-irradiation of the assembly can be considered after examination. Significant changes have been made to the buildings and the hoist facilities for handling very heavy flasks. It was necessary to rearrange the handling, machining and in-cell storage facilities. The development of an inspection rig will make it possible, some time in 1980, to carry out non destructive tests of assemblies, optical and metrological examination of assemblies prior to dismantling or of the structure after dismantling [fr

A spent fuel assemblies monitoring device by nondestructive analysis 'PYTHON'

International Nuclear Information System (INIS)

Saad, M.; Broeskamp, M.; Hahn, H.; Bignan, G.; Boisset, M.; Silie, P.

1995-01-01

The monitoring of spent fuel assemblies (16 x 16 UOX) in KWG-reactor pool with the use of non-destructive methods (total Gamma and neutron counting) allow the control of average burn-up and the extremity burn-up. The measurements allow a safety-criticality control before loading the fuel assemblies into the transport casks. A device called PYTHON has been tested and qualified in France. This paper presents a description of the industrial PYTHON device and the results of the measurements. (orig.)

Hybrid reduced order modeling for assembly calculations

Energy Technology Data Exchange (ETDEWEB)

Bang, Youngsuk, E-mail: ysbang00@fnctech.com [FNC Technology, Co. Ltd., Yongin-si (Korea, Republic of); Abdel-Khalik, Hany S., E-mail: abdelkhalik@purdue.edu [Purdue University, West Lafayette, IN (United States); Jessee, Matthew A., E-mail: jesseema@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mertyurek, Ugur, E-mail: mertyurek@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2015-12-15

Highlights: • Reducing computational cost in engineering calculations. • Reduced order modeling algorithm for multi-physics problem like assembly calculation. • Non-intrusive algorithm with random sampling. • Pattern recognition in the components with high sensitive and large variation. - Abstract: While the accuracy of assembly calculations has considerably improved due to the increase in computer power enabling more refined description of the phase space and use of more sophisticated numerical algorithms, the computational cost continues to increase which limits the full utilization of their effectiveness for routine engineering analysis. Reduced order modeling is a mathematical vehicle that scales down the dimensionality of large-scale numerical problems to enable their repeated executions on small computing environment, often available to end users. This is done by capturing the most dominant underlying relationships between the model's inputs and outputs. Previous works demonstrated the use of the reduced order modeling for a single physics code, such as a radiation transport calculation. This manuscript extends those works to coupled code systems as currently employed in assembly calculations. Numerical tests are conducted using realistic SCALE assembly models with resonance self-shielding, neutron transport, and nuclides transmutation/depletion models representing the components of the coupled code system.

Hybrid reduced order modeling for assembly calculations

International Nuclear Information System (INIS)

Bang, Youngsuk; Abdel-Khalik, Hany S.; Jessee, Matthew A.; Mertyurek, Ugur

2015-01-01

Highlights: • Reducing computational cost in engineering calculations. • Reduced order modeling algorithm for multi-physics problem like assembly calculation. • Non-intrusive algorithm with random sampling. • Pattern recognition in the components with high sensitive and large variation. - Abstract: While the accuracy of assembly calculations has considerably improved due to the increase in computer power enabling more refined description of the phase space and use of more sophisticated numerical algorithms, the computational cost continues to increase which limits the full utilization of their effectiveness for routine engineering analysis. Reduced order modeling is a mathematical vehicle that scales down the dimensionality of large-scale numerical problems to enable their repeated executions on small computing environment, often available to end users. This is done by capturing the most dominant underlying relationships between the model's inputs and outputs. Previous works demonstrated the use of the reduced order modeling for a single physics code, such as a radiation transport calculation. This manuscript extends those works to coupled code systems as currently employed in assembly calculations. Numerical tests are conducted using realistic SCALE assembly models with resonance self-shielding, neutron transport, and nuclides transmutation/depletion models representing the components of the coupled code system.

Installation, test and non-linear vibratory analysis of an experiment with four fuel assembly models under axial flow

International Nuclear Information System (INIS)

Clement, Simon

2014-01-01

The present study is in the scope of pressurized water reactors (PWR) core response to earthquakes. The goal of this thesis is to measure the coupling between fuel assemblies caused an axial water flow. The design, production and installation a new test facility named ICARE EXPERIMENTAL are presented. ICARE EXPERIMENTAL was built in order to measure simultaneously the vibrations of four fuel assemblies (2 x 2) under an axial flow. Vibrations are produced by imposing the dynamic of one of the fuel assemblies and the displacements of the three others, induced by the fluid, are measured in the horizontal plane at grids level. A new data analysis method combining time-frequency analysis and orthogonal mode decomposition (POD) is described. This method, named Sliding Window POD (SWPOD), allows analysing multicomponent data, of which spatial repartition of energy and frequency content are time dependent. In the case of mechanical systems (linear and nonlinear), the link between the proper orthogonal modes obtained through SWPOD and the normal modes (linear and nonlinear) is studied. The SWPOD is applied to experimental tests of a steam generators U-tube, showing the appearance of internal resonances. The method is also applied to dynamic experimental tests of a fuel assembly under axial flow, the evolution of its normal modes is obtained as a function of the fluid velocity. The measures acquired with the ICARE EXPERIMENTAL installation are analysed using the SWPOD. The first results show characteristic behavior of the free fuel assemblies at their resonances. The coupling between fuel assemblies, induced by the fluid, is reproduced by simulations performed using the COEUR3D code. This code is based on a porous media model in order to simulate a fuel assemblies network under axial flow. (author) [fr

Diversity, assembly and regulation of archaeal type IV pili-like and non-type-IV pili-like surface structures.

Science.gov (United States)

Lassak, Kerstin; Ghosh, Abhrajyoti; Albers, Sonja-Verena

2012-01-01

Archaea have evolved fascinating surface structures allowing rapid adaptation to changing environments. The archaeal surface appendages display such diverse biological roles as motility, adhesion, biofilm formation, exchange of genetic material and species-specific interactions and, in turn, increase fitness of the cells. Intriguingly, despite sharing the same functions with their bacterial counterparts, the assembly mechanism of many archaeal surface structures is rather related to assembly of bacterial type IV pili. This review summarizes our state-of-the-art knowledge about unique structural and biochemical properties of archaeal surface appendages with a particular focus on archaeal type IV pili-like structures. The latter comprise not only widely distributed archaella (formerly known as archaeal flagella), but also different highly specialized archaeal pili, which are often restricted to certain species. Recent findings regarding assembly mechanisms, structural aspects and physiological roles of these type IV pili-like structures will be discussed in detail. Recently, first regulatory proteins involved in transition from both planktonic to sessile lifestyle and in assembly of archaella were identified. To conclude, we provide novel insights into regulatory mechanisms underlying the assembly of archaeal surface structures. Copyright © 2012. Published by Elsevier Masson SAS.

Mobius Assembly: A versatile Golden-Gate framework towards universal DNA assembly.

Directory of Open Access Journals (Sweden)

Andreas I Andreou

Full Text Available Synthetic biology builds upon the foundation of engineering principles, prompting innovation and improvement in biotechnology via a design-build-test-learn cycle. A community-wide standard in DNA assembly would enable bio-molecular engineering at the levels of predictivity and universality in design and construction that are comparable to other engineering fields. Golden Gate Assembly technology, with its robust capability to unidirectionally assemble numerous DNA fragments in a one-tube reaction, has the potential to deliver a universal standard framework for DNA assembly. While current Golden Gate Assembly frameworks (e.g. MoClo and Golden Braid render either high cloning capacity or vector toolkit simplicity, the technology can be made more versatile-simple, streamlined, and cost/labor-efficient, without compromising capacity. Here we report the development of a new Golden Gate Assembly framework named Mobius Assembly, which combines vector toolkit simplicity with high cloning capacity. It is based on a two-level, hierarchical approach and utilizes a low-frequency cutter to reduce domestication requirements. Mobius Assembly embraces the standard overhang designs designated by MoClo, Golden Braid, and Phytobricks and is largely compatible with already available Golden Gate part libraries. In addition, dropout cassettes encoding chromogenic proteins were implemented for cost-free visible cloning screening that color-code different cloning levels. As proofs of concept, we have successfully assembled up to 16 transcriptional units of various pigmentation genes in both operon and multigene arrangements. Taken together, Mobius Assembly delivers enhanced versatility and efficiency in DNA assembly, facilitating improved standardization and automation.

Programmed Nanomaterial Assemblies in Large Scales: Applications of Synthetic and Genetically- Engineered Peptides to Bridge Nano-Assemblies and Macro-Assemblies

Energy Technology Data Exchange (ETDEWEB)

Matsui, Hiroshi

2014-09-09

Work is reported in these areas: Large-scale & reconfigurable 3D structures of precise nanoparticle assemblies in self-assembled collagen peptide grids; Binary QD-Au NP 3D superlattices assembled with collagen-like peptides and energy transfer between QD and Au NP in 3D peptide frameworks; Catalytic peptides discovered by new hydrogel-based combinatorial phage display approach and their enzyme-mimicking 2D assembly; New autonomous motors of metal-organic frameworks (MOFs) powered by reorganization of self-assembled peptides at interfaces; Biomimetic assembly of proteins into microcapsules on oil-in-water droplets with structural reinforcement via biomolecular recognition-based cross-linking of surface peptides; and Biomimetic fabrication of strong freestanding genetically-engineered collagen peptide films reinforced by quantum dot joints. We gained the broad knowledge about biomimetic material assembly from nanoscale to microscale ranges by coassembling peptides and NPs via biomolecular recognition. We discovered: Genetically-engineered collagen-like peptides can be self-assembled with Au NPs to generate 3D superlattices in large volumes (> μm{sup 3}); The assembly of the 3D peptide-Au NP superstructures is dynamic and the interparticle distance changes with assembly time as the reconfiguration of structure is triggered by pH change; QDs/NPs can be assembled with the peptide frameworks to generate 3D superlattices and these QDs/NPs can be electronically coupled for the efficient energy transfer; The controlled assembly of catalytic peptides mimicking the catalytic pocket of enzymes can catalyze chemical reactions with high selectivity; and, For the bacteria-mimicking swimmer fabrication, peptide-MOF superlattices can power translational and propellant motions by the reconfiguration of peptide assembly at the MOF-liquid interface.

Electrical Quality Assurance of the Superconducting Circuits during LHC Machine Assembly

CERN Document Server

Bozzini, D; Desebe, O; Mess, K H; Russenschuck, Stephan; Bednarek, M; Dworak, D; Górnicki, E; Jurkiewicz, P; Kapusta, P; Kotarba, A; Ludwin, J; Olek, S; Talach, M; Zieblinski, M; Klisch, M; Prochal, B

2008-01-01

Based on the LHC powering reference database, all-together 1750 superconducting circuits were connected in the various cryogenic transfer lines of the LHC machine. Testing the continuity, magnet polarity, and the quality of the electrical insulation were the main tasks of the Electrical Quality Assurance (ELQA) activities during the LHC machine assembly. With the assembly of the LHC now complete, the paper reviews the work flow, resources, and the qualification results including the different types of electrical non-conformities.

Anisotropic Self-Assembly of Organic–Inorganic Hybrid Microtoroids

KAUST Repository

Al-Rehili, Safa’a

2016-10-24

Toroidal structures based on self-assembly of predesigned building blocks are well-established in the literature, but spontaneous self-organization to prepare such structures has not been reported to date. Here, organic–inorganic hybrid microtoroids synthesized by simultaneous coordination-driven assembly of amphiphilic molecules and hydrophilic polymers are reported. Mixing amphiphilic molecules with iron(III) chloride and hydrophilic polymers in water leads, within minutes, to the formation of starlike nanostructures. A spontaneous self-organization of these nanostructures is then triggered to form stable hybrid microtoroids. Interestingly, the toroids exhibit anisotropic hierarchical growth, giving rise to a layered toroidal framework. These microstructures are mechanically robust and can act as templates to host metallic nanoparticles such as gold and silver. Understanding the nature of spontaneous assembly driven by coordination multiple non-covalent interactions can help explain the well-ordered complexity of many biological organisms in addition to expanding the available tools to mimic such structures at a molecular level.

Self-assembly of self-assembled molecular triangles

Indian Academy of Sciences (India)

While the solution state structure of 1 can be best described as a trinuclear complex, in the solidstate well-fashioned intermolecular - and CH- interactions are observed. Thus, in the solid-state further self-assembly of already self-assembled molecular triangle is witnessed. The triangular panels are arranged in a linear ...

Evaluation of nine popular de novo assemblers in microbial genome assembly.

Science.gov (United States)

Forouzan, Esmaeil; Maleki, Masoumeh Sadat Mousavi; Karkhane, Ali Asghar; Yakhchali, Bagher

2017-12-01

Next generation sequencing (NGS) technologies are revolutionizing biology, with Illumina being the most popular NGS platform. Short read assembly is a critical part of most genome studies using NGS. Hence, in this study, the performance of nine well-known assemblers was evaluated in the assembly of seven different microbial genomes. Effect of different read coverage and k-mer parameters on the quality of the assembly were also evaluated on both simulated and actual read datasets. Our results show that the performance of assemblers on real and simulated datasets could be significantly different, mainly because of coverage bias. According to outputs on actual read datasets, for all studied read coverages (of 7×, 25× and 100×), SPAdes and IDBA-UD clearly outperformed other assemblers based on NGA50 and accuracy metrics. Velvet is the most conservative assembler with the lowest NGA50 and error rate. Copyright © 2017. Published by Elsevier B.V.

Spatio-temporal Dynamics and Mechanisms of Stress Granule Assembly.

Directory of Open Access Journals (Sweden)

Daisuke Ohshima

2015-06-01

Full Text Available Stress granules (SGs are non-membranous cytoplasmic aggregates of mRNAs and related proteins, assembled in response to environmental stresses such as heat shock, hypoxia, endoplasmic reticulum (ER stress, chemicals (e.g. arsenite, and viral infections. SGs are hypothesized as a loci of mRNA triage and/or maintenance of proper translation capacity ratio to the pool of mRNAs. In brain ischemia, hippocampal CA3 neurons, which are resilient to ischemia, assemble SGs. In contrast, CA1 neurons, which are vulnerable to ischemia, do not assemble SGs. These results suggest a critical role SG plays in regards to cell fate decisions. Thus SG assembly along with its dynamics should determine the cell fate. However, the process that exactly determines the SG assembly dynamics is largely unknown. In this paper, analyses of experimental data and computer simulations were used to approach this problem. SGs were assembled as a result of applying arsenite to HeLa cells. The number of SGs increased after a short latent period, reached a maximum, then decreased during the application of arsenite. At the same time, the size of SGs grew larger and became localized at the perinuclear region. A minimal mathematical model was constructed, and stochastic simulations were run to test the modeling. Since SGs are discrete entities as there are only several tens of them in a cell, commonly used deterministic simulations could not be employed. The stochastic simulations replicated observed dynamics of SG assembly. In addition, these stochastic simulations predicted a gamma distribution relative to the size of SGs. This same distribution was also found in our experimental data suggesting the existence of multiple fusion steps in the SG assembly. Furthermore, we found that the initial steps in the SG assembly process and microtubules were critical to the dynamics. Thus our experiments and stochastic simulations presented a possible mechanism regulating SG assembly.

A conceptual design of assembly strategy and dedicated tools for assembly of 40o sector

International Nuclear Information System (INIS)

Park, H.K.; Nam, K.O.; Kim, D.J.; Ahn, H.J.; Lee, J.H.; Im, K.; Shaw, R.

2010-01-01

The International Thermanuclear Experimental Reactor (ITER) tokamak device is composed of 9 vacuum vessel (VV)/toroidal field coils (TFCs)/vacuum vessel thermal shields (VVTS) 40 o sectors. Each VV/TFCs/VVTS 40 o sector is made up of one 40 o VV, two 20 o TFCs and associated VVTS segments. The 40 o sectors are sub-assembled at assembly hall respectively and then nine 40 o sectors sub-assembled at assembly hall are finally assembled at tokamak in-pit hall. The assembly strategy and tools for the 40 o sector sub-assembly and final assembly should be developed to satisfy the basic assembly requirements of the ITER tokamak device. Accordingly, the purpose-built assembly tools should be designed and manufactured considering assembly plan, available space, cost, safety, easy operation, efficient maintenance, and so on. The 40 o sector assembly tools are classified into 2 groups. One group is the sub-assembly tools including upending tool, lifting tool, sub-assembly tool, VV supports and bracing tools used at assembly hall and the other group is the in-pit assembly tools including lifting tool, central column, radial beams and their supports. This paper describes the current status of the assembly strategy and major tools for the VV/TFCs/VVTS 40 o sector assembly at in-pit hall and assembly hall. The conceptual design of the major assembly tools and assembly process at assembly hall and tokamak in-pit hall are presented also.

Formation of self-assembled stripes on the anodic aluminum oxide

International Nuclear Information System (INIS)

Liu Hongwen; Guo Haiming; Wang Yeliang; Shen Chengmin; Yang Haitao; Wang Yutian; Wei Long

2004-01-01

Non-polished aluminum sheets were anodized and the coexistence of self-assembled stripes and porous arrays on the Al surface was observed. The nanostructures were investigated in details using an atomic force microscope. And the formation mechanism of the stripes was discussed and simulated using Brusselator model in this work. The authors demonstrated that the self-assembled patterns on the Al surface were governed by the competition of formation and dissolution of alumina film during the reaction process. Moreover, this type of ordered structure could only form in certain conditions

Fuel injection assembly for use in turbine engines and method of assembling same

Science.gov (United States)

Berry, Jonathan Dwight; Johnson, Thomas Edward; York, William David; Uhm, Jong Ho

2015-12-15

A fuel injection assembly for use in a turbine engine is provided. The fuel injection assembly includes an end cover, an endcap assembly, a fluid supply chamber, and a plurality of tube assemblies positioned at the endcap assembly. Each of the tube assemblies includes housing having a fuel plenum and a cooling fluid plenum. The cooling fluid plenum is positioned downstream from the fuel plenum and separated from the fuel plenum by an intermediate wall. The plurality of tube assemblies also include a plurality of tubes that extends through the housing. Each of the plurality of tubes is coupled in flow communication with the fluid supply chamber and a combustion chamber positioned downstream from the tube assembly. The plurality of tube assemblies further includes an aft plate at a downstream end of the cooling fluid plenum. The plate includes at least one aperture.

RNA-seq de novo Assembly Reveals Differential Gene Expression in Glossina palpalis gambiensis Infected with Trypanosoma brucei gambiense vs. Non-Infected and Self-Cured Flies.

Science.gov (United States)

Hamidou Soumana, Illiassou; Klopp, Christophe; Ravel, Sophie; Nabihoudine, Ibouniyamine; Tchicaya, Bernadette; Parrinello, Hugues; Abate, Luc; Rialle, Stéphanie; Geiger, Anne

2015-01-01

Trypanosoma brucei gambiense (Tbg), causing the sleeping sickness chronic form, completes its developmental cycle within the tsetse fly vector Glossina palpalis gambiensis (Gpg) before its transmission to humans. Within the framework of an anti-vector disease control strategy, a global gene expression profiling of trypanosome infected (susceptible), non-infected, and self-cured (refractory) tsetse flies was performed, on their midguts, to determine differential genes expression resulting from in vivo trypanosomes, tsetse flies (and their microbiome) interactions. An RNAseq de novo assembly was achieved. The assembled transcripts were mapped to reference sequences for functional annotation. Twenty-four percent of the 16,936 contigs could not be annotated, possibly representing untranslated mRNA regions, or Gpg- or Tbg-specific ORFs. The remaining contigs were classified into 65 functional groups. Only a few transposable elements were present in the Gpg midgut transcriptome, which may represent active transpositions and play regulatory roles. One thousand three hundred and seventy three genes differentially expressed (DEGs) between stimulated and non-stimulated flies were identified at day-3 post-feeding; 52 and 1025 between infected and self-cured flies at 10 and 20 days post-feeding, respectively. The possible roles of several DEGs regarding fly susceptibility and refractoriness are discussed. The results provide new means to decipher fly infection mechanisms, crucial to develop anti-vector control strategies.

AutoAssemblyD: a graphical user interface system for several genome assemblers.

Science.gov (United States)

Veras, Adonney Allan de Oliveira; de Sá, Pablo Henrique Caracciolo Gomes; Azevedo, Vasco; Silva, Artur; Ramos, Rommel Thiago Jucá

2013-01-01

Next-generation sequencing technologies have increased the amount of biological data generated. Thus, bioinformatics has become important because new methods and algorithms are necessary to manipulate and process such data. However, certain challenges have emerged, such as genome assembly using short reads and high-throughput platforms. In this context, several algorithms have been developed, such as Velvet, Abyss, Euler-SR, Mira, Edna, Maq, SHRiMP, Newbler, ALLPATHS, Bowtie and BWA. However, most such assemblers do not have a graphical interface, which makes their use difficult for users without computing experience given the complexity of the assembler syntax. Thus, to make the operation of such assemblers accessible to users without a computing background, we developed AutoAssemblyD, which is a graphical tool for genome assembly submission and remote management by multiple assemblers through XML templates. AssemblyD is freely available at https://sourceforge.net/projects/autoassemblyd. It requires Sun jdk 6 or higher.

Measurement of M{sup 3} and k{sub {infinity}} for heavy water natural uranium assembly

Energy Technology Data Exchange (ETDEWEB)

Popovic, D; Raisic, N; Markovic, H; Takac, S; Zdravkovic, Z; Lolic, B [Boris Kidric Institute of Nuclear Sciences, Vinca, Beograd (Yugoslavia)

1959-03-15

The migration length M and the infinite multiplication factor k{sub {infinity}} of the heavy water-natural uranium bare assembly are determined by measuring the reactivity of the reactor as function of the heavy water level. Since the assembly is non reflected the results obtained are of relatively high accuracy. (author)

Development of non-linear TWB parts

Energy Technology Data Exchange (ETDEWEB)

Lee, J.; Yoon, C.S.; Lim, J.D. [Hyundai Motor Company and Kia Motors Corp. (Korea). Advanced Technology Center; Park, H.C. [Hyundai Hysco (Korea). Technical Research Lab.

2005-07-01

New manufacturing methods have applied for automotive parts to reduce total weight of car, resulting in improvement of fuel efficiency. TWB technique is applied to auto body parts, especially door inner, side inner and outer panel, and center floor panel to accomplish this goal. We applied non-linear (circular welded) TWB to shock absorber housing (to reduce total weight of shock absorber housing assembly). Welding line and shape of blank were determined by FEM analysis. High formability steel sheet and 440MPa grade high strength steel sheet were laser welded and press formed to final shock absorber housing (S/ABS HSG) panel and assembled with other sub parts. As a result, more than 10% of total weight of shock absorber housing assembly could be reduced compared with the mass of same part manufactured by conventional method. Also circular welding technique made it possible to design optimum welding line of TWB part. This paper is about result of FEM analysis and development procedure of non-linear TWB part (shock absorber housing assembly). (orig.)

Emerging Insights into Directed Assembly: Taking Examples from Nature to Design Synthetic Processes

Science.gov (United States)

de Pablo, Juan J.

There is considerable interest in controlling the assembly of polymeric material in order to create highly ordered materials for applications. Such materials are often trapped in metastable, non-equilibrium states, and the processes through which they assemble become an important aspect of the materials design strategy. An example is provided by di-block copolymer directed self-assembly, where a decade of work has shown that, through careful choice of process variables, it is possible to create ordered structures whose degree of perfection meets the constraints of commercial semiconductor manufacturing. As impactful as that work has been, it has focused on relatively simple materials neutral polymers, consisting of two or at most three blocks. Furthermore, the samples that have been produced have been limited to relatively thin films, and the assembly has been carried out on ideal, two-dimensional substrates. The question that arises now is whether one can translate those achievements to polymeric materials having a richer sequence, to monomers that include charges, to three-dimensional substrates, or to active systems that are in a permanent non-equilibrium state. Building on discoveries from the biophysics literature, this presentation will review recent work from our group and others that explains how nature has evolved to direct the assembly of nucleic acids into intricate, fully three-dimensional macroscopic functional materials that are not only active, but also responsive to external cues. We will discuss how principles from polymer physics serve to explain those assemblies, and how one might design a new generation of synthetic systems that incorporate some of those principles.

Assembly, alignment and test of the Transiting Exoplanet Survey Satellite (TESS) optical assemblies

Science.gov (United States)

Balonek, Gregory; Brown, Joshua J.; Andre, James E.; Chesbrough, Christian D.; Chrisp, Michael P.; Dalpiaz, Michael; Lennon, Joseph; Richards, B. C.; Clark, Kristin E.

2017-08-01

The Transiting Exoplanet Survey Satellite (TESS) will carry four visible waveband, seven-element, refractive F/1.4 lenses, each with a 34 degree diagonal field of view. This paper describes the methods used for the assembly, alignment and test of the four flight optical assemblies. Prior to commencing the build of the four flight optical assemblies, a Risk Reduction Unit (RRU) was successfully assembled and tested [1]. The lessons learned from the RRU were applied to the build of the flight assemblies. The main modifications to the flight assemblies include the inking of the third lens element stray light mitigation, tighter alignment tolerances, and diamond turning for critical mechanical surfaces. Each of the optical assemblies was tested interferometrically and measured with a low coherence distance measuring interferometer (DMI) to predict the optimal shim thickness between the lens assembly and detector before -75°C environmental testing. In addition to individual test data, environmental test results from prior assemblies allow for the exploration of marginal performance differences between each of the optical assemblies.

SWAP-Assembler: scalable and efficient genome assembly towards thousands of cores.

Science.gov (United States)

Meng, Jintao; Wang, Bingqiang; Wei, Yanjie; Feng, Shengzhong; Balaji, Pavan

2014-01-01

There is a widening gap between the throughput of massive parallel sequencing machines and the ability to analyze these sequencing data. Traditional assembly methods requiring long execution time and large amount of memory on a single workstation limit their use on these massive data. This paper presents a highly scalable assembler named as SWAP-Assembler for processing massive sequencing data using thousands of cores, where SWAP is an acronym for Small World Asynchronous Parallel model. In the paper, a mathematical description of multi-step bi-directed graph (MSG) is provided to resolve the computational interdependence on merging edges, and a highly scalable computational framework for SWAP is developed to automatically preform the parallel computation of all operations. Graph cleaning and contig extension are also included for generating contigs with high quality. Experimental results show that SWAP-Assembler scales up to 2048 cores on Yanhuang dataset using only 26 minutes, which is better than several other parallel assemblers, such as ABySS, Ray, and PASHA. Results also show that SWAP-Assembler can generate high quality contigs with good N50 size and low error rate, especially it generated the longest N50 contig sizes for Fish and Yanhuang datasets. In this paper, we presented a highly scalable and efficient genome assembly software, SWAP-Assembler. Compared with several other assemblers, it showed very good performance in terms of scalability and contig quality. This software is available at: https://sourceforge.net/projects/swapassembler.

Assembly tool design

International Nuclear Information System (INIS)

Kanamori, Naokazu; Nakahira, Masataka; Ohkawa, Yoshinao; Tada, Eisuke; Seki, Masahiro

1996-06-01

The reactor core of the International Thermonuclear Experimental Reactor (ITER) is assembled with a number of large and asymmetric components within a tight tolerance in order to assure the structural integrity for various loads and to provide the tritium confinement. In addition, the assembly procedure should be compatible with remote operation since the core structures will be activated by 14-MeV neutrons once it starts operation and thus personal access will be prohibited. Accordingly, the assembly procedure and tool design are quite essential and should be designed from the beginning to facilitate remote operation. According to the ITER Design Task Agreement, the Japan Atomic Energy Research Institute (JAERI) has performed design study to develop the assembly procedures and associated tool design for the ITER tokamak assembly. This report describes outlines of the assembly tools and the remaining issues obtained in this design study. (author)

Drive piston assembly for a valve actuator assembly

Science.gov (United States)

Sun, Zongxuan

2010-02-23

A drive piston assembly is provided that is operable to selectively open a poppet valve. The drive piston assembly includes a cartridge defining a generally stepped bore. A drive piston is movable within the generally stepped bore and a boost sleeve is coaxially disposed with respect to the drive piston. A main fluid chamber is at least partially defined by the generally stepped bore, drive piston, and boost sleeve. First and second feedback chambers are at least partially defined by the drive piston and each are disposed at opposite ends of the drive piston. At least one of the drive piston and the boost sleeve is sufficiently configured to move within the generally stepped bore in response to fluid pressure within the main fluid chamber to selectively open the poppet valve. A valve actuator assembly and engine are also provided incorporating the disclosed drive piston assembly.

Verification of the enrichment of fresh VVER-440 fuel assemblies at NPP Paks

Energy Technology Data Exchange (ETDEWEB)

Almasia, I.; Hlavathya, Z.; Nguyena, C. T. [Institute of Isotopes, Hungarian Academy of Sciences, Budapest, (Hungary); others, and

2012-06-15

A Non Destructive Analysis (NDA) method was developed for the verification of {sup 235}U enrichment of both homogeneous and profiled VVER-440 reactor fresh fuel assemblies by means of gamma spectrometry. A total of ca. 30 assemblies were tested, five of which were homogeneous, with {sup 235}U enrichment in the range 1,6% to 3,6%, while the others were profiled with pins of 3,3% to 4,4% enrichment. Two types of gamma detectors were used for the test measurements: 2 coaxial HPGe detectors and a miniature CdZnTe (CZT) detector fitting into the central tube of the assemblies. It was therefore possible to obtain information from both the inside and the outside of the assemblies. It was shown that it is possible to distinguish between different types of assemblies within a reasonable measurement time (about 1000 sec). For the HPGe measurements the assemblies had to be lifted out from their storage rack, while for the CZT detector measurements the assemblies could be left at their storage position, as it was shown that the neighbouring assemblies do not affect measurement inside the assemblies' central tube. The measured values were compared to Monte Carlo simulations carried out using the MCNP code, and a recommendation for the optimal approach to verify the {sup 235}U enrichment of fresh VVER-440 reactor fuel assemblies is suggested.

Full scale tests on remote handled FFTF fuel assembly waste handling and packaging

International Nuclear Information System (INIS)

Allen, C.R.; Cash, R.J.; Dawson, S.A.; Strode, J.N.

1986-01-01

Handling and packaging of remote handled, high activity solid waste fuel assembly hardware components from spent FFTF reactor fuel assemblies have been evaluated using full scale components. The demonstration was performed using FFTF fuel assembly components and simulated components which were handled remotely using electromechanical manipulators, shielding walls, master slave manipulators, specially designed grapples, and remote TV viewing. The testing and evaluation included handling, packaging for current and conceptual shipping containers, and the effects of volume reduction on packing efficiency and shielding requirements. Effects of waste segregation into transuranic (TRU) and non-transuranic fractions also are discussed

The Replacement of 10 Non-Conserved Residues in the Core Protein of JFH-1 Hepatitis C Virus Improves Its Assembly and Secretion.

Directory of Open Access Journals (Sweden)

Loïc Etienne

Full Text Available Hepatitis C virus (HCV assembly is still poorly understood. It is thought that trafficking of the HCV core protein to the lipid droplet (LD surface is essential for its multimerization and association with newly synthesized HCV RNA to form the viral nucleocapsid. We carried out a mapping analysis of several complete HCV genomes of all genotypes, and found that the genotype 2 JFH-1 core protein contained 10 residues different from those of other genotypes. The replacement of these 10 residues of the JFH-1 strain sequence with the most conserved residues deduced from sequence alignments greatly increased virus production. Confocal microscopy of the modified JFH-1 strain in cell culture showed that the mutated JFH-1 core protein, C10M, was present mostly at the endoplasmic reticulum (ER membrane, but not at the surface of the LDs, even though its trafficking to these organelles was possible. The non-structural 5A protein of HCV was also redirected to ER membranes and colocalized with the C10M core protein. Using a Semliki forest virus vector to overproduce core protein, we demonstrated that the C10M core protein was able to form HCV-like particles, unlike the native JFH-1 core protein. Thus, the substitution of a few selected residues in the JFH-1 core protein modified the subcellular distribution and assembly properties of the protein. These findings suggest that the early steps of HCV assembly occur at the ER membrane rather than at the LD surface. The C10M-JFH-1 strain will be a valuable tool for further studies of HCV morphogenesis.

Ecological drivers of community assembly across taxonomic groups and trophic levels

DEFF Research Database (Denmark)

Özkan, Korhan

assembly is a complex phenomenon driven by the interplay between environmental species sorting, ecological interactions between species and dispersal, linking local communities with the surrounding communities as well as with their regional populations. Although the research on community assembly....... Local bird abundance was strongly linked with occupancy across the metacommunity (the bird communities in the Istranca landscape) as well as the species’ regional population and range size across the western Palearctic. Null model analyses showed that bird occupancy was non-randomly related to species...... environmental niche. Furthermore, species abundance and occupancy across both the metacommunity and the whole western Palearctic were significantly related to an independent species specialization index calculated for the French birds. Together these results indicated that forest bird community assembly...

Self-assembled nanostructures

CERN Document Server

Zhang, Jin Z; Liu, Jun; Chen, Shaowei; Liu, Gang-yu

2003-01-01

Nanostructures refer to materials that have relevant dimensions on the nanometer length scales and reside in the mesoscopic regime between isolated atoms and molecules in bulk matter. These materials have unique physical properties that are distinctly different from bulk materials. Self-Assembled Nanostructures provides systematic coverage of basic nanomaterials science including materials assembly and synthesis, characterization, and application. Suitable for both beginners and experts, it balances the chemistry aspects of nanomaterials with physical principles. It also highlights nanomaterial-based architectures including assembled or self-assembled systems. Filled with in-depth discussion of important applications of nano-architectures as well as potential applications ranging from physical to chemical and biological systems, Self-Assembled Nanostructures is the essential reference or text for scientists involved with nanostructures.

Modular assembly of transposable element arrays by microsatellite targeting in the guayule and rice genomes.

Science.gov (United States)

Valdes Franco, José A; Wang, Yi; Huo, Naxin; Ponciano, Grisel; Colvin, Howard A; McMahan, Colleen M; Gu, Yong Q; Belknap, William R

2018-04-19

Guayule (Parthenium argentatum A. Gray) is a rubber-producing desert shrub native to Mexico and the United States. Guayule represents an alternative to Hevea brasiliensis as a source for commercial natural rubber. The efficient application of modern molecular/genetic tools to guayule improvement requires characterization of its genome. The 1.6 Gb guayule genome was sequenced, assembled and annotated. The final 1.5 Gb assembly, while fragmented (N 50  = 22 kb), maps > 95% of the shotgun reads and is essentially complete. Approximately 40,000 transcribed, protein encoding genes were annotated on the assembly. Further characterization of this genome revealed 15 families of small, microsatellite-associated, transposable elements (TEs) with unexpected chromosomal distribution profiles. These SaTar (Satellite Targeted) elements, which are non-autonomous Mu-like elements (MULEs), were frequently observed in multimeric linear arrays of unrelated individual elements within which no individual element is interrupted by another. This uniformly non-nested TE multimer architecture has not been previously described in either eukaryotic or prokaryotic genomes. Five families of similarly distributed non-autonomous MULEs (microsatellite associated, modularly assembled) were characterized in the rice genome. Families of TEs with similar structures and distribution profiles were identified in sorghum and citrus. The sequencing and assembly of the guayule genome provides a foundation for application of current crop improvement technologies to this plant. In addition, characterization of this genome revealed SaTar elements with distribution profiles unique among TEs. Satar targeting appears based on an alternative MULE recombination mechanism with the potential to impact gene evolution.

Nuclear fuel assembly

International Nuclear Information System (INIS)

Hirano, Yasushi; Hirukawa, Koji; Sakurada, Koichi.

1994-01-01

A bundle of fuel rods is divided into four fuel rod group regions of small fuel rod bundles by a cross-shaped partitioning structure consisting of paired plate-like structures which connect two opposing surfaces of a channel box. A water removing material with less neutron absorption (for example, Zr or a Zr alloy) or a solid moderator is inserted and secured to a portion of a non-boiling water region interposed between the paired plate-like structure. It has a structure that light water flows to the region in the plate-like structure. The volume, density or composition of the water removing material is controlled depending on the composition of the fuels, to change the moderating characteristics of neutrons in the non-boiling water region. This can easily moderate the difference of nuclear characteristics between each of fuel assemblies using fuel materials of different fuel compositions. Further, the reactivity control effect of the burnable poisons can be enhanced without worsening fuel economy or linear power density. (I.N.)

The study of postural workload in assembly of furniture upholstery

Directory of Open Access Journals (Sweden)

Marek Lasota Andrzej

2017-01-01

Full Text Available The productivity of the workers is affected by the Work-related Musculoskeletal Disorders (WRMSDs which common cause of health problems, sick leave and it can result in decreased quality of work and increased absenteeism. The objective of this study is to evaluate and investigate the postural workload of sewing machine operators in the assembly of upholstery in furniture factory by using the Ovako Working Posture Analysing System (OWAS with sampling. The results indicated that posture code 2111 (back code: 2 – bent forward; arms code: 1 – both below the shoulder joint; legs code: 1 – sitting position; load code: – 1 less than 10 kg was the most common working posture rating 38.1%; 63.9% of positions displayed non-neutral back postures and 52% received harmful action categories. The performed assembly tasks have an influence on harmless and harmful action categories. This study is crucial on assembly, and in the future work allows develop a framework for assessment the physical risk of WRMSDs in assembly.

Facility for protection of technological, especially power assemblies

International Nuclear Information System (INIS)

Cichon, S.; Hahn, J.; Malatek, K.; Randak, O.; Vitovec, P.; Zidek, M.

1987-01-01

The facility consists of sensors producing analog signals, used as input information for the evaluation of process conditions or equipment failures. The sensors are fitted to partial functional parts of technological assemblies, such as nuclear reactors. The individual sensors are connected via unification converters to the respective protection units. The facility is resistant to breakdowns of the analog sensors and other components including the computer; it features the possibility of in-service failure detection and the capability of immediate regeneration following a failure. This capability prevents, with high probability, the production of non-accident failures of the technological assembly. The block diagram is described of the facility and its operation in the event of an emergency. (J.B.). 1 fig

Newnes electronics assembly handbook

CERN Document Server

Brindley, Keith

2013-01-01

Newnes Electronics Assembly Handbook: Techniques, Standards and Quality Assurance focuses on the aspects of electronic assembling. The handbook first looks at the printed circuit board (PCB). Base materials, basic mechanical properties, cleaning of assemblies, design, and PCB manufacturing processes are then explained. The text also discusses surface mounted assemblies and packaging of electromechanical assemblies, as well as the soldering process. Requirements for the soldering process; solderability and protective coatings; cleaning of PCBs; and mass solder/component reflow soldering are des

Directed self-assembly of nanogold using a chemically modified nanopatterned surface

Science.gov (United States)

Nidetz, Robert; Kim, Jinsang

2012-02-01

Electron-beam lithography (EBL) was used to define an aminosilane nanopatterned surface in order to electrostatically self-assemble gold nanoparticles (Au NPs). The chemically modified nanopatterned surfaces were immersed into a Au NP solution to allow the Au NPs to self-assemble. Equilibrium self-assembly was achieved in only 20 min. The number of Au NPs that self-assembled on an aminosilane dot was controlled by manipulating the diameters of both the Au NPs and the dots. Adding salt to the Au NP solution enabled the Au NPs to self-assemble in greater numbers on the same sized dot. However, the preparation of the Au NP solution containing salt was sensitive to spikes in the salt concentration. These spikes led to aggregation of the Au NPs and non-specific deposition of Au NPs on the substrate. The Au NP patterned surfaces were immersed in a sodium hydroxide solution in order to lift-off the patterned Au NPs, but no lift-off was observed without adequate physical agitation. The van der Waals forces are too strong to allow for lift-off despite the absence of electrostatic forces.

Directed self-assembly of nanogold using a chemically modified nanopatterned surface

International Nuclear Information System (INIS)

Nidetz, Robert; Kim, Jinsang

2012-01-01

Electron-beam lithography (EBL) was used to define an aminosilane nanopatterned surface in order to electrostatically self-assemble gold nanoparticles (Au NPs). The chemically modified nanopatterned surfaces were immersed into a Au NP solution to allow the Au NPs to self-assemble. Equilibrium self-assembly was achieved in only 20 min. The number of Au NPs that self-assembled on an aminosilane dot was controlled by manipulating the diameters of both the Au NPs and the dots. Adding salt to the Au NP solution enabled the Au NPs to self-assemble in greater numbers on the same sized dot. However, the preparation of the Au NP solution containing salt was sensitive to spikes in the salt concentration. These spikes led to aggregation of the Au NPs and non-specific deposition of Au NPs on the substrate. The Au NP patterned surfaces were immersed in a sodium hydroxide solution in order to lift-off the patterned Au NPs, but no lift-off was observed without adequate physical agitation. The van der Waals forces are too strong to allow for lift-off despite the absence of electrostatic forces. (paper)

Non-uniform self-assembly: On the anisotropic architecture of α-synuclein supra-fibrillar aggregates.

Science.gov (United States)

Semerdzhiev, Slav A; Shvadchak, Volodymyr V; Subramaniam, Vinod; Claessens, Mireille M A E

2017-08-09

Although the function of biopolymer hydrogels in nature depends on structural anisotropy at mesoscopic length scales, the self-assembly of such anisotropic structures in vitro is challenging. Here we show that fibrils of the protein α-synuclein spontaneously self-assemble into structurally anisotropic hydrogel particles. While the fibrils in the interior of these supra-fibrillar aggregates (SFAs) are randomly oriented, the fibrils in the periphery prefer to cross neighboring fibrils at high angles. This difference in organization coincides with a significant difference in polarity of the environment in the central and peripheral parts of the SFA. We rationalize the structural anisotropy of SFAs in the light of the observation that αS fibrils bind a substantial amount of counterions. We propose that, with the progress of protein polymerization into fibrils, this binding of counterions changes the ionic environment which triggers a change in fibril organization resulting in anisotropy in the architecture of hydrogel particles.

Fuel Assembly Damping Summary

Energy Technology Data Exchange (ETDEWEB)

Lee, Kanghee; Kang, Heungseok; Oh, Dongseok; Yoon, Kyungho; Kim, Hyungkyu; Kim, Jaeyong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

This paper summary the fuel assembly damping data in air/in still water/under flow, released from foreign fuel vendors, compared our data with the published data. Some technical issues in fuel assembly damping measurement testing are also briefly discussed. Understanding of each fuel assembly damping mechanisms according to the surrounding medium and flow velocity can support the fuel design improvement in fuel assembly dynamics and structural integrity aspect. Because the upgraded requirements of the newly-developed advanced reactor system will demands to minimize fuel design margin in integrity evaluation, reduction in conservatism of fuel assembly damping can contribute to alleviate the fuel design margin for sure. Damping is an energy dissipation mechanism in a vibrating mechanical structure and prevents a resonant structure from having infinite vibration amplitudes. The sources of fuel assembly damping are various from support friction to flow contribution, and it can be increased by the viscosity or drag of surrounding fluid medium or the average velocity of water flowing. Fuel licensing requires fuel design evaluation in transient or accidental condition. Dynamic response analysis of fuel assembly is to show fuel integrity and requires information on assembly-wise damping in dry condition and under wet or water flowing condition. However, damping measurement test for the full-scale fuel assembly prototype is not easy to carry out because of the scale (fuel prototype, test facility), unsteadiness of test data (scattering, random sampling and processing), instrumentation under water flowing (water-proof response measurement), and noise. LWR fuel technology division in KAERI is preparing the infra structure for damping measurement test of full-scale fuel assembly, to support fuel industries and related research activities. Here is a preliminary summary of fuel assembly damping, published in the literature. Some technical issues in fuel assembly damping

Fuel assembly

International Nuclear Information System (INIS)

Abe, Hideaki; Sakai, Takao; Ishida, Tomio; Yokota, Norikatsu.

1992-01-01

The lower ends of a plurality of plate-like shape memory alloys are secured at the periphery of the upper inside of the handling head of a fuel assembly. As the shape memory alloy, a Cu-Zn alloy, a Ti-Pd alloy or a Fe-Ni alloy is used. When high temperature coolants flow out to the handling head, the shape memory alloy deforms by warping to the outer side more greatly toward the upper portion thereof with the temperature increase of the coolants. As the result, the shape of the flow channel of the coolants is changed so as to enlarge at the exit of the upper end of the fuel assembly. Then, the pressure loss of the coolants in the fuel assembly is decreased by the enlargement. Accordingly, the flow rate of the coolants in the fuel assembly is increased to lower the temperature of the coolants. Further, high temperature coolants and low temperature coolants are mixed sufficiently just above the fuel assembly. This can suppress the temperature fluctuation of the mixed coolants in the upper portion of the reactor core, thereby enabling to decrease a fatigue and failures of the structural components in the upper portion of the reactor core. (I.N.)

Soldering in electronics assembly

CERN Document Server

Judd, Mike

2013-01-01

Soldering in Electronics Assembly discusses several concerns in soldering of electronic assemblies. The book is comprised of nine chapters that tackle different areas in electronic assembly soldering. Chapter 1 discusses the soldering process itself, while Chapter 2 covers the electronic assemblies. Chapter 3 talks about solders and Chapter 4 deals with flux. The text also tackles the CS and SC soldering process. The cleaning of soldered assemblies, solder quality, and standards and specifications are also discussed. The book will be of great use to professionals who deal with electronic assem

Cytochrome oxidase assembly does not require catalytically active cytochrome C.

Science.gov (United States)

Barrientos, Antoni; Pierre, Danielle; Lee, Johnson; Tzagoloff, Alexander

2003-03-14

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the transfer of electrons from reduced cytochrome c to molecular oxygen. COX assembly requires the coming together of nuclear- and mitochondrial-encoded subunits and the assistance of a large number of nuclear gene products acting at different stages of maturation of the enzyme. In Saccharomyces cerevisiae, expression of cytochrome c, encoded by CYC1 and CYC7, is required not only for electron transfer but also for COX assembly through a still unknown mechanism. We have attempted to distinguish between a functional and structural requirement of cytochrome c in COX assembly. A cyc1/cyc7 double null mutant strain was transformed with the cyc1-166 mutant gene (Schweingruber, M. E., Stewart, J. W., and Sherman, F. (1979) J. Biol. Chem. 254, 4132-4143) that expresses stable but catalytically inactive iso-1-cytochrome c. The COX content of the cyc1/cyc7 double mutant strain harboring non-functional iso-1-cytochrome c has been characterized spectrally, functionally, and immunochemically. The results of these studies demonstrate that cytochrome c plays a structural rather than functional role in assembly of cytochrome c oxidase. In addition to its requirement for COX assembly, cytochrome c also affects turnover of the enzyme. Mutants containing wild type apocytochrome c in mitochondria lack COX, suggesting that only the folded and mature protein is able to promote COX assembly.

Multivalent protein assembly using monovalent self-assembling building blocks

NARCIS (Netherlands)

Petkau - Milroy, K.; Sonntag, M.H.; Colditz, A.; Brunsveld, L.

2013-01-01

Discotic molecules, which self-assemble in water into columnar supramolecular polymers, emerged as an alternative platform for the organization of proteins. Here, a monovalent discotic decorated with one single biotin was synthesized to study the self-assembling multivalency of this system in regard

Bearing assemblies, apparatuses, and motor assemblies using the same

Science.gov (United States)

Sexton, Timothy N.; Cooley, Craig H.; Knuteson, Cody W.

2015-12-29

Various embodiments of the invention relate to bearing assemblies, apparatuses and motor assemblies that include geometric features configured to impart a selected amount of heat transfer and/or hydrodynamic film formation. In an embodiment, a bearing assembly may include a plurality of superhard bearing pads distributed circumferentially about an axis. At least some of the plurality of superhard bearing pads may include a plurality of sub-superhard bearing elements defining a bearing surface. At least some of the plurality of sub-superhard bearing elements may be spaced from one another by one or more voids to impart a selected amount of heat transfer and hydrodynamic film formation thereon during operation. The bearing assembly may also include a support ring that carries the plurality of superhard bearing pads. In addition, at least a portion of the sub-superhard bearing elements may extend beyond the support ring.

Fuel assembly

International Nuclear Information System (INIS)

Gjertsen, R.K.; Bassler, E.A.; Huckestein, E.A.; Salton, R.B.; Tower, S.N.

1988-01-01

A fuel assembly adapted for use with a pressurized water nuclear reactor having capabilities for fluid moderator spectral shift control is described comprising: parallel arranged elongated nuclear fuel elements; means for providing for axial support of the fuel elements and for arranging the fuel elements in a spaced array; thimbles interspersed among the fuel elements adapted for insertion of a rod control cluster therewithin; means for structurally joining the fuel elements and the guide thimbles; fluid moderator control means for providing a volume of low neutron absorbing fluid within the fuel assembly and for removing a substantially equivalent volume of reactor coolant water therefrom, a first flow manifold at one end of the fuel assembly sealingly connected to a first end of the moderator control tubes whereby the first ends are commonly flow connected; and a second flow manifold, having an inlet passage and an outlet passage therein, sealingly connected to a second end of the moderator control tubes at a second end of the fuel assembly

Self assembly of organic nanostructures and dielectrophoretic assembly of inorganic nanowires.

Science.gov (United States)

Dholakia, Geetha; Kuo, Steven; Allen, E. L.

2007-03-01

Self assembly techniques enable the organization of organic molecules into nanostructures. Currently engineering strategies for efficient assembly and routine integration of inorganic nanoscale objects into functional devices is very limited. AC Dielectrophoresis is an efficient technique to manipulate inorganic nanomaterials into higher dimensional structures. We used an alumina template based sol-gel synthesis method for the growth of various metal oxide nanowires with typical diameters of 100-150 nm, ranging in length from 3-10 μm. Here we report the dielectrophoretic assembly of TiO2 nanowires, an important material for photocatalysis and photovoltaics, onto interdigitated devices. Self assembly in organic nanostructures and its dependence on structure and stereochemistry of the molecule and dielectrophoretic field dependence in the assembly of inorganic nanowires will be compared and contrasted. Tunneling spectroscopy and DOS of these nanoscale systems will also be discussed.

Architecture and assembly of the Bacillus subtilis spore coat.

Science.gov (United States)

Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J

2014-01-01

Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of "nanodot" particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization

Architecture and Assembly of the Bacillus subtilis Spore Coat

Science.gov (United States)

Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J.

2014-01-01

Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of “nanodot” particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization

Fire resistant PV shingle assembly

Science.gov (United States)

Lenox, Carl J.

2012-10-02

A fire resistant PV shingle assembly includes a PV assembly, including PV body, a fire shield and a connection member connecting the fire shield below the PV body, and a support and inter-engagement assembly. The support and inter-engagement assembly is mounted to the PV assembly and comprises a vertical support element, supporting the PV assembly above a support surface, an upper interlock element, positioned towards the upper PV edge, and a lower interlock element, positioned towards the lower PV edge. The upper interlock element of one PV shingle assembly is inter-engageable with the lower interlock element of an adjacent PV shingle assembly. In some embodiments the PV shingle assembly may comprise a ventilation path below the PV body. The PV body may be slidably mounted to the connection member to facilitate removal of the PV body.

Mechanobiological induction of long-range contractility by diffusing biomolecules and size scaling in cell assemblies

Science.gov (United States)

Dasbiswas, K.; Alster, E.; Safran, S. A.

2016-06-01

Mechanobiological studies of cell assemblies have generally focused on cells that are, in principle, identical. Here we predict theoretically the effect on cells in culture of locally introduced biochemical signals that diffuse and locally induce cytoskeletal contractility which is initially small. In steady-state, both the concentration profile of the signaling molecule as well as the contractility profile of the cell assembly are inhomogeneous, with a characteristic length that can be of the order of the system size. The long-range nature of this state originates in the elastic interactions of contractile cells (similar to long-range “macroscopic modes” in non-living elastic inclusions) and the non-linear diffusion of the signaling molecules, here termed mechanogens. We suggest model experiments on cell assemblies on substrates that can test the theory as a prelude to its applicability in embryo development where spatial gradients of morphogens initiate cellular development.

Structural basis of the pH-dependent assembly of a botulinum neurotoxin complex.

Science.gov (United States)

Matsui, Tsutomu; Gu, Shenyan; Lam, Kwok-Ho; Carter, Lester G; Rummel, Andreas; Mathews, Irimpan I; Jin, Rongsheng

2014-11-11

Botulinum neurotoxins (BoNTs) are among the most poisonous biological substances known. They assemble with non-toxic non-hemagglutinin (NTNHA) protein to form the minimally functional progenitor toxin complexes (M-PTC), which protects BoNT in the gastrointestinal tract and releases it upon entry into the circulation. Here we provide molecular insight into the assembly between BoNT/A and NTNHA-A using small-angle X-ray scattering. We found that the free form BoNT/A maintains a pH-independent conformation with limited domain flexibility. Intriguingly, the free form NTNHA-A adopts pH-dependent conformational changes due to a torsional motion of its C-terminal domain. Once forming a complex at acidic pH, they each adopt a stable conformation that is similar to that observed in the crystal structure of the M-PTC. Our results suggest that assembly of the M-PTC depends on the environmental pH and that the complex form of BoNT/A is induced by interacting with NTNHA-A at acidic pH. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Marmonier, Pierre; Mesnage, Bernard; Nervi, J.C.

1975-01-01

This invention refers to fuel assemblies for a liquid metal cooled fast neutron reactor. Each assembly is composed of a hollow vertical casing, of regular polygonal section, containing a bundle of clad pins filled with a fissile or fertile substance. The casing is open at its upper end and has a cylindrical foot at its lower end for positioning the assembly in a housing provided in the horizontal diagrid, on which the core assembly rests. A set of flat bars located on the external surface of the casing enables it to be correctly orientated in its housing among the other core assemblies [fr

PREFACE The physics of virus assembly The physics of virus assembly

Science.gov (United States)

Stockley, Peter G.; Twarock, Reidun

2010-12-01

Viruses are pathogens in every kingdom of life and are major causes of human disease and suffering. They are known to encompass a size range that overlaps with that of the smallest bacterial cells, and the largest viruses now seem to be hosts of their own viral pathogens. Recent genomic sequencing efforts show that many organisms have genes that are likely to be descended in evolution from viral progenitors. Even more astonishingly, analysis of the world's oceans has shown that some of the simplest viruses, the tailed dsDNA phages, are the most common biological entities on the planet, with estimates of their numbers ranging up to 1031, with ~ 1021 infection events every second, leading to a turnover of around 20% of the biomass in the sea every few days. These cycles of infection and lysis of oceanic bacteria and algae provide the nutrients for the smallest organisms lying at the bottom of the food chain. Without viruses, therefore, life on Earth would probably not be sustainable. These are remarkable facts for systems that are non-living in the strict sense, and are composed of simple materials—nucleic acids, proteins and lipids. Many viruses consist of little more than a protective protein coat surrounding their genomic nucleic acids, which can be either DNA or RNA. Their simplicity leads to highly symmetrical structures with protein containers based on helical or icosahedral lattices. Many simple viruses self-assemble rapidly and with great fidelity, and many groups are busy trying to exploit these properties to make virus-like particles for a wide range of applications, including targeted drug-delivery, medical imaging and even novel materials. This issue of Physical Biology contains a series of papers describing some of the latest experimental and theoretical research on viruses, their structures and assembly, as well as their regulated disassembly during infection. These range from a dissection of the in vivo assembly mechanism of a filamentous virus

Methods for estimating the reliability of the RBMK fuel assemblies and elements

International Nuclear Information System (INIS)

Klemin, A.I.; Sitkarev, A.G.

1985-01-01

Applied non-parametric methods for calculation of point and interval estimations for the basic nomenclature of reliability factors for the RBMK fuel assemblies and elements are described. As the fuel assembly and element reliability factors, the average lifetime is considered at a preset operating time up to unloading due to fuel burnout as well as the average lifetime at the reactor transient operation and at the steady-state fuel reloading mode of reactor operation. The formulae obtained are included into the special standardized engineering documentation

Self assembly of rectangular shapes on concentration programming and probabilistic tile assembly models.

Science.gov (United States)

Kundeti, Vamsi; Rajasekaran, Sanguthevar

2012-06-01

Efficient tile sets for self assembling rectilinear shapes is of critical importance in algorithmic self assembly. A lower bound on the tile complexity of any deterministic self assembly system for an n × n square is [Formula: see text] (inferred from the Kolmogrov complexity). Deterministic self assembly systems with an optimal tile complexity have been designed for squares and related shapes in the past. However designing [Formula: see text] unique tiles specific to a shape is still an intensive task in the laboratory. On the other hand copies of a tile can be made rapidly using PCR (polymerase chain reaction) experiments. This led to the study of self assembly on tile concentration programming models. We present two major results in this paper on the concentration programming model. First we show how to self assemble rectangles with a fixed aspect ratio ( α:β ), with high probability, using Θ( α + β ) tiles. This result is much stronger than the existing results by Kao et al. (Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008) and Doty (Randomized self-assembly for exact shapes. In: proceedings of the 50th annual IEEE symposium on foundations of computer science (FOCS), IEEE, Atlanta. pp 85-94, 2009)-which can only self assembly squares and rely on tiles which perform binary arithmetic. On the other hand, our result is based on a technique called staircase sampling . This technique eliminates the need for sub-tiles which perform binary arithmetic, reduces the constant in the asymptotic bound, and eliminates the need for approximate frames (Kao et al. Randomized self-assembly for approximate shapes, LNCS, vol 5125. Springer, Heidelberg, 2008). Our second result applies staircase sampling on the equimolar concentration programming model (The tile complexity of linear assemblies. In: proceedings of the 36th international colloquium automata, languages and programming: Part I on ICALP '09, Springer-Verlag, pp 235

Micellar Self-Assembly of Block Copolymers for Fabrication of Nanostructured Membranes

KAUST Repository

Marques, Debora S.

2013-01-01

of immersion in a non-solvent bath. These mechanisms are driven thermodynamically but are limited by kinetic factors. It is shown in this work how the ordering of the assembly of micelles is improved by the solution parameters such as solvent quality

Assembling large, complex environmental metagenomes

Energy Technology Data Exchange (ETDEWEB)

Howe, A. C. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Plant Soil and Microbial Sciences; Jansson, J. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division; Malfatti, S. A. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Tringe, S. G. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Tiedje, J. M. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Plant Soil and Microbial Sciences; Brown, C. T. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Computer Science and Engineering

2012-12-28

The large volumes of sequencing data required to sample complex environments deeply pose new challenges to sequence analysis approaches. De novo metagenomic assembly effectively reduces the total amount of data to be analyzed but requires significant computational resources. We apply two pre-assembly filtering approaches, digital normalization and partitioning, to make large metagenome assemblies more computationaly tractable. Using a human gut mock community dataset, we demonstrate that these methods result in assemblies nearly identical to assemblies from unprocessed data. We then assemble two large soil metagenomes from matched Iowa corn and native prairie soils. The predicted functional content and phylogenetic origin of the assembled contigs indicate significant taxonomic differences despite similar function. The assembly strategies presented are generic and can be extended to any metagenome; full source code is freely available under a BSD license.

Transuranic Hybrid Materials: Crystallographic and Computational Metrics of Supramolecular Assembly

Energy Technology Data Exchange (ETDEWEB)

Surbella, Robert G. [Department; Ducati, Lucas C. [Department; Pellegrini, Kristi L. [Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States; McNamara, Bruce K. [Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States; Autschbach, Jochen [Department; Schwantes, Jon M. [Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99354, United States; Cahill, Christopher L. [Department

2017-07-26

A family of twelve supramolecular [AnO2Cl4]2- (An = U, Np, Pu) containing compounds assembled via hydrogen and halogen bonds donated by substituted 4-X-pyridinium cations (X = H, Cl, Br, I) is reported. These materials were prepared from a room-temperature synthesis wherein crystallization of unhydrolyzed and valence pure [An(VI)O2Cl4]2- (An = U, Np, Pu) tectons are the norm. We present a hierarchy of assembly criteria based on crystallographic observations, and subsequently quantify the strengths of the non-covalent interactions using Kohn-Sham density functional calculations. We provide, for the first time, a detailed description of the electrostatic potentials (ESPs) of the actinyl tetrahalide dianions and reconcile crystallographically observed structural motifs and non-covalent interaction (NCI) acceptor-donor pairings. Our findings indicate that the average electrostatic potential across the halogen ligands (the acceptors) changes by only ~2 kJ mol-1 across the AnO22+ series, indicating the magnitude of the potential is independent of the metal center. The role of the cation is therefore critical in directing structural motifs and dictating the resulting hydrogen and halogen bond strengths, the former being stronger due to the positive charge centralized on the pyridyl nitrogen N-H+. Subsequent analyses using the Quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) approaches support this conclusion and highlight the structure directing role of the cations. Whereas one can infer that the 2 Columbic attraction is the driver for assembly, the contribution of the non-covalent interaction is to direct the molecular-level arrangement (or disposition) of the tectons.

Amyloid Structure and Assembly: Insights from Scanning Transmission Electron Microscopy

Energy Technology Data Exchange (ETDEWEB)

Goldsbury, C.; Wall, J.; Baxa, U.; Simon, M. N.; Steven, A. C.; Engel, A.; Aebi, U.; Muller, S. A.

2011-01-01

Amyloid fibrils are filamentous protein aggregates implicated in several common diseases such as Alzheimer's disease and type II diabetes. Similar structures are also the molecular principle of the infectious spongiform encephalopathies such as Creutzfeldt-Jakob disease in humans, scrapie in sheep, and of the so-called yeast prions, inherited non-chromosomal elements found in yeast and fungi. Scanning transmission electron microscopy (STEM) is often used to delineate the assembly mechanism and structural properties of amyloid aggregates. In this review we consider specifically contributions and limitations of STEM for the investigation of amyloid assembly pathways, fibril polymorphisms and structural models of amyloid fibrils. This type of microscopy provides the only method to directly measure the mass-per-length (MPL) of individual filaments. Made on both in vitro assembled and ex vivo samples, STEM mass measurements have illuminated the hierarchical relationships between amyloid fibrils and revealed that polymorphic fibrils and various globular oligomers can assemble simultaneously from a single polypeptide. The MPLs also impose strong constraints on possible packing schemes, assisting in molecular model building when combined with high-resolution methods like solid-state nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR).

Nuclear fuel string assembly

International Nuclear Information System (INIS)

Ip, A.K.; Koyanagi, K.; Tarasuk, W.R.

1976-01-01

A method of fabricating rodded fuels suitable for use in pressure tube type reactors and in pressure vessel type reactors is described. Fuel rods are secured as an inner and an outer sub-assembly, each rod attached between mounting rings secured to the rod ends. The two sub-assemblies are telescoped together and positioned by spaced thimbles located between them to provide precise positioning while permittng differential axial movement between the sub-assemblies. Such sub-assemblies are particularly suited for mounting as bundle strings. The method provides particular advantages in the assembly of annular-section fuel pins, which includes booster fuel containing enriched fuel material. (LL)

Improvement of flame resistance of non-flame retardant cables by applying fire protection measures

International Nuclear Information System (INIS)

Takemura, Yujiro; Segoshi, Yoshinori; Jinno, Susumu; Mii, Kazuki

2017-01-01

The new regulatory requirements, which were put in force after the Fukushima Daiichi accident, impose the use of flame retardant cables on the plant components having safety functions for the purpose of fire protection. However, some Japanese nuclear power plants built in the early days use non-flame retardant cables that do not pass the demonstration test to check for the flame resistance. To cope with the new regulatory requirements, a fire protection measure for non-flame retardant cables was introduced to assure flame resistance of non-flame retardant cables equivalent to or higher than that of flame retardant cables. To illustrate the fire protection measure, both non-flame retardant cables and its cable tray are covered with fire protection sheet fabricated from incombustible material to form an assembly. Considering the demonstration test results, it can be concluded that flame resistance performance of non-flame retardant cables equivalent to or higher than that of flame retardant cables can be assured by forming the assembly even if an external fire outside the assembly and internal cable fire inside the assembly are assumed. This paper introduces the design of the assembly consisting of a bundle of cables and a cable tray and summarizes the results of demonstration tests. (author)

Fuel assembly reconstitution

International Nuclear Information System (INIS)

Morgado, Mario M.; Oliveira, Monica G.N.; Ferreira Junior, Decio B.M.; Santos, Barbara O. dos; Santos, Jorge E. dos

2009-01-01

Fuel failures have been happened in Nuclear Power Plants worldwide, without lost of integrity and safety, mainly for the public, environment and power plants workers. The most common causes of these events are corrosion (CRUD), fretting and pellet cladding interaction. These failures are identified by increasing the activity of fission products, verified by chemical analyses of reactor coolant. Through these analyses, during the fourth operation cycle of Angra 2 Nuclear Power Plant, was possible to observe fuel failure indication. This indication was confirmed in the end of the cycle during the unloading of reactor core through leakage tests of fuel assembly, using the equipment called 'In Mast Sipping' and 'Box Sipping'. After confirmed, the fuel assembly reconstitution was scheduled, and happened in April, 2007, where was identified the cause and the fuel rod failure, which was substitute by dummy rods (zircaloy). The cause was fretting by 'debris'. The actions to avoid and prevent fuel assemblies failures are important. The goals of this work are to describe the methodology of fuel assembly reconstitution using the FARE (Fuel Assembly Reconstitution Equipment) system, to describe the results of this task in economic and security factors of the company and show how the fuel assembly failures are identified during operation and during the outage. (author)

Reliability Testing the Die-Attach of CPV Cell Assemblies

Energy Technology Data Exchange (ETDEWEB)

Bosco, N.; Sweet, C.; Kurtz, S.

2011-02-01

Results and progress are reported for a course of work to establish an efficient reliability test for the die-attach of CPV cell assemblies. Test vehicle design consists of a ~1 cm2 multijunction cell attached to a substrate via several processes. A thermal cycling sequence is developed in a test-to-failure protocol. Methods of detecting a failed or failing joint are prerequisite for this work; therefore both in-situ and non-destructive methods, including infrared imaging techniques, are being explored as a method to quickly detect non-ideal or failing bonds.

An Efficient Procedure for Removal and Inactivation of Alpha-Synuclein Assemblies from Laboratory Materials.

Science.gov (United States)

Bousset, Luc; Brundin, Patrik; Böckmann, Anja; Meier, Beat; Melki, Ronald

2016-01-01

Preformed α-synuclein fibrils seed the aggregation of soluble α-synuclein in cultured cells and in vivo. This, and other findings, has kindled the idea that α-synuclein fibrils possess prion-like properties. As α-synuclein fibrils should not be considered as innocuous, there is a need for decontamination and inactivation procedures for laboratory benches and non-disposable laboratory material. We assessed the effectiveness of different procedures designed to disassemble α-synuclein fibrils and reduce their infectivity. We examined different commercially available detergents to remove α-synuclein assemblies adsorbed on materials that are not disposable and that are most found in laboratories (e.g. plastic, glass, aluminum or stainless steel surfaces). We show that methods designed to decrease PrP prion infectivity neither effectively remove α-synuclein assemblies adsorbed to different materials commonly used in the laboratory nor disassemble the fibrillar form of the protein with efficiency. In contrast, both commercial detergents and SDS detached α-synuclein assemblies from contaminated surfaces and disassembled the fibrils. We describe three cleaning procedures that effectively remove and disassemble α-synuclein seeds. The methods rely on the use of detergents that are compatible with most non-disposable tools in a laboratory. The procedures are easy to implement and significantly decrease any potential risks associated to handling α-synuclein assemblies.

Reflector-moderated critical assemblies

International Nuclear Information System (INIS)

Paxton, H.C.; Jarvis, G.A.; Byers, C.C.

1975-07-01

Experiments with reflector-moderated critical assemblies were part of the Rover Program at the Los Alamos Scientific Laboratory (LASL). These assemblies were characterized by thick D 2 O or beryllium reflectors surrounding large cavities that contained highly enriched uranium at low average densities. Because interest in this type of system has been revived by LASL Plasma Cavity Assembly studies, more detailed descriptions of the early assemblies than had been available in the unclassified literature are provided. (U.S.)

SWAP-Assembler 2: Optimization of De Novo Genome Assembler at Large Scale

Energy Technology Data Exchange (ETDEWEB)

Meng, Jintao; Seo, Sangmin; Balaji, Pavan; Wei, Yanjie; Wang, Bingqiang; Feng, Shengzhong

2016-08-16

In this paper, we analyze and optimize the most time-consuming steps of the SWAP-Assembler, a parallel genome assembler, so that it can scale to a large number of cores for huge genomes with the size of sequencing data ranging from terabyes to petabytes. According to the performance analysis results, the most time-consuming steps are input parallelization, k-mer graph construction, and graph simplification (edge merging). For the input parallelization, the input data is divided into virtual fragments with nearly equal size, and the start position and end position of each fragment are automatically separated at the beginning of the reads. In k-mer graph construction, in order to improve the communication efficiency, the message size is kept constant between any two processes by proportionally increasing the number of nucleotides to the number of processes in the input parallelization step for each round. The memory usage is also decreased because only a small part of the input data is processed in each round. With graph simplification, the communication protocol reduces the number of communication loops from four to two loops and decreases the idle communication time. The optimized assembler is denoted as SWAP-Assembler 2 (SWAP2). In our experiments using a 1000 Genomes project dataset of 4 terabytes (the largest dataset ever used for assembling) on the supercomputer Mira, the results show that SWAP2 scales to 131,072 cores with an efficiency of 40%. We also compared our work with both the HipMER assembler and the SWAP-Assembler. On the Yanhuang dataset of 300 gigabytes, SWAP2 shows a 3X speedup and 4X better scalability compared with the HipMer assembler and is 45 times faster than the SWAP-Assembler. The SWAP2 software is available at https://sourceforge.net/projects/swapassembler.

Polymer Directed Protein Assemblies

NARCIS (Netherlands)

van Rijn, Patrick

2013-01-01

Protein aggregation and protein self-assembly is an important occurrence in natural systems, and is in some form or other dictated by biopolymers. Very obvious influences of biopolymers on protein assemblies are, e. g., virus particles. Viruses are a multi-protein assembly of which the morphology is

Recovery of reactor electrical assemblies using differential de-encapsulation to remove dielectric insulation systems

International Nuclear Information System (INIS)

Hubrig, J.G.; Hammerstone, E.B.

1986-01-01

State-of-the-art de-encapsulation technologies associated with the conventional dielectric insulation systems employed in the construction of electrical coils and power distribution systems do not allow for accurate fatigue/failure analysis or reliable recovery of costly assembly components. Differential de-encapsulation allows for the selective removal of contemporary thermoset resin based insulation systems to allow non-destructive penetration of insulation wall thicknesses to both examine critical areas and recover high performance metallic and non-metallic inserts for remanufacture; significantly reducing replacement costs and reactor downtime. The authors' analysis describes how the availability of engineering data from the selective and non-destructive removal of insulation materials will aid in the evaluation of original manufacture, materials and procedures; enabling redesign to enhance subsequent on line performance. They also discuss why the ability to recover coil and core assemblies for remanufacture will have a major economic impact on reactor management costs

Core/coil assembly for use in superconducting magnets and method for assembling the same

Science.gov (United States)

Kassner, David A.

1979-01-01

A core/coil assembly for use in a superconducting magnet of the focusing or bending type used in syncronous particle accelerators comprising a coil assembly contained within an axial bore of the stacked, washer type, carbon steel laminations which comprise the magnet core assembly, and forming an interference fit with said laminations at the operating temperature of said magnet. Also a method for making such core/coil assemblies comprising the steps of cooling the coil assembly to cryogenic temperatures and drawing it rapidly upwards into the bore of said stacked laminations.

A pipeline for the de novo assembly of the Themira biloba (Sepsidae: Diptera) transcriptome using a multiple k-mer length approach.

Science.gov (United States)

Melicher, Dacotah; Torson, Alex S; Dworkin, Ian; Bowsher, Julia H

2014-03-12

The Sepsidae family of flies is a model for investigating how sexual selection shapes courtship and sexual dimorphism in a comparative framework. However, like many non-model systems, there are few molecular resources available. Large-scale sequencing and assembly have not been performed in any sepsid, and the lack of a closely related genome makes investigation of gene expression challenging. Our goal was to develop an automated pipeline for de novo transcriptome assembly, and to use that pipeline to assemble and analyze the transcriptome of the sepsid Themira biloba. Our bioinformatics pipeline uses cloud computing services to assemble and analyze the transcriptome with off-site data management, processing, and backup. It uses a multiple k-mer length approach combined with a second meta-assembly to extend transcripts and recover more bases of transcript sequences than standard single k-mer assembly. We used 454 sequencing to generate 1.48 million reads from cDNA generated from embryo, larva, and pupae of T. biloba and assembled a transcriptome consisting of 24,495 contigs. Annotation identified 16,705 transcripts, including those involved in embryogenesis and limb patterning. We assembled transcriptomes from an additional three non-model organisms to demonstrate that our pipeline assembled a higher-quality transcriptome than single k-mer approaches across multiple species. The pipeline we have developed for assembly and analysis increases contig length, recovers unique transcripts, and assembles more base pairs than other methods through the use of a meta-assembly. The T. biloba transcriptome is a critical resource for performing large-scale RNA-Seq investigations of gene expression patterns, and is the first transcriptome sequenced in this Dipteran family.

The Mammalian Cell Cycle Regulates Parvovirus Nuclear Capsid Assembly

Science.gov (United States)

Riolobos, Laura; Domínguez, Carlos; Kann, Michael; Almendral, José M.

2015-01-01

It is unknown whether the mammalian cell cycle could impact the assembly of viruses maturing in the nucleus. We addressed this question using MVM, a reference member of the icosahedral ssDNA nuclear parvoviruses, which requires cell proliferation to infect by mechanisms partly understood. Constitutively expressed MVM capsid subunits (VPs) accumulated in the cytoplasm of mouse and human fibroblasts synchronized at G0, G1, and G1/S transition. Upon arrest release, VPs translocated to the nucleus as cells entered S phase, at efficiencies relying on cell origin and arrest method, and immediately assembled into capsids. In synchronously infected cells, the consecutive virus life cycle steps (gene expression, proteins nuclear translocation, capsid assembly, genome replication and encapsidation) proceeded tightly coupled to cell cycle progression from G0/G1 through S into G2 phase. However, a DNA synthesis stress caused by thymidine irreversibly disrupted virus life cycle, as VPs became increasingly retained in the cytoplasm hours post-stress, forming empty capsids in mouse fibroblasts, thereby impairing encapsidation of the nuclear viral DNA replicative intermediates. Synchronously infected cells subjected to density-arrest signals while traversing early S phase also blocked VPs transport, resulting in a similar misplaced cytoplasmic capsid assembly in mouse fibroblasts. In contrast, thymidine and density arrest signals deregulating virus assembly neither perturbed nuclear translocation of the NS1 protein nor viral genome replication occurring under S/G2 cycle arrest. An underlying mechanism of cell cycle control was identified in the nuclear translocation of phosphorylated VPs trimeric assembly intermediates, which accessed a non-conserved route distinct from the importin α2/β1 and transportin pathways. The exquisite cell cycle-dependence of parvovirus nuclear capsid assembly conforms a novel paradigm of time and functional coupling between cellular and virus life

Nuclear fuel assemblies and fuel pins usable in such assemblies

International Nuclear Information System (INIS)

Jolly, R.

1982-01-01

A novel end cap for a nuclear fuel assembly is described in detail. It consists of a trisection arrangement which is received within a cell of a cellular grid. The cell contains abutment means with which the trisection comes into abutment. The grid also contains an abutment means for preventing the trisections from being inserted into the cell in an incorrect orientation. The present design allows fuel pins to be securely held in a hold-down grid of a sub-assembly. The design also allows easier dis-assembly of the swollen and embrittled fuel pins prior to reprocessing. (U.K.)

Icarus: visualizer for de novo assembly evaluation.

Science.gov (United States)

Mikheenko, Alla; Valin, Gleb; Prjibelski, Andrey; Saveliev, Vladislav; Gurevich, Alexey

2016-11-01

: Data visualization plays an increasingly important role in NGS data analysis. With advances in both sequencing and computational technologies, it has become a new bottleneck in genomics studies. Indeed, evaluation of de novo genome assemblies is one of the areas that can benefit from the visualization. However, even though multiple quality assessment methods are now available, existing visualization tools are hardly suitable for this purpose. Here, we present Icarus-a novel genome visualizer for accurate assessment and analysis of genomic draft assemblies, which is based on the tool QUAST. Icarus can be used in studies where a related reference genome is available, as well as for non-model organisms. The tool is available online and as a standalone application. http://cab.spbu.ru/software/icarus CONTACT: aleksey.gurevich@spbu.ruSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Rapid centriole assembly in Naegleria reveals conserved roles for both de novo and mentored assembly.

Science.gov (United States)

Fritz-Laylin, Lillian K; Levy, Yaron Y; Levitan, Edward; Chen, Sean; Cande, W Zacheus; Lai, Elaine Y; Fulton, Chandler

2016-03-01

Centrioles are eukaryotic organelles whose number and position are critical for cilia formation and mitosis. Many cell types assemble new centrioles next to existing ones ("templated" or mentored assembly). Under certain conditions, centrioles also form without pre-existing centrioles (de novo). The synchronous differentiation of Naegleria amoebae to flagellates represents a unique opportunity to study centriole assembly, as nearly 100% of the population transitions from having no centrioles to having two within minutes. Here, we find that Naegleria forms its first centriole de novo, immediately followed by mentored assembly of the second. We also find both de novo and mentored assembly distributed among all major eukaryote lineages. We therefore propose that both modes are ancestral and have been conserved because they serve complementary roles, with de novo assembly as the default when no pre-existing centriole is available, and mentored assembly allowing precise regulation of number, timing, and location of centriole assembly. © 2016 Wiley Periodicals, Inc.

Next-generation transcriptome assembly

Energy Technology Data Exchange (ETDEWEB)

Martin, Jeffrey A.; Wang, Zhong

2011-09-01

Transcriptomics studies often rely on partial reference transcriptomes that fail to capture the full catalog of transcripts and their variations. Recent advances in sequencing technologies and assembly algorithms have facilitated the reconstruction of the entire transcriptome by deep RNA sequencing (RNA-seq), even without a reference genome. However, transcriptome assembly from billions of RNA-seq reads, which are often very short, poses a significant informatics challenge. This Review summarizes the recent developments in transcriptome assembly approaches - reference-based, de novo and combined strategies-along with some perspectives on transcriptome assembly in the near future.

De Novo Assembly of Human Herpes Virus Type 1 (HHV-1) Genome, Mining of Non-Canonical Structures and Detection of Novel Drug-Resistance Mutations Using Short- and Long-Read Next Generation Sequencing Technologies.

Science.gov (United States)

Karamitros, Timokratis; Harrison, Ian; Piorkowska, Renata; Katzourakis, Aris; Magiorkinis, Gkikas; Mbisa, Jean Lutamyo

2016-01-01

Human herpesvirus type 1 (HHV-1) has a large double-stranded DNA genome of approximately 152 kbp that is structurally complex and GC-rich. This makes the assembly of HHV-1 whole genomes from short-read sequencing data technically challenging. To improve the assembly of HHV-1 genomes we have employed a hybrid genome assembly protocol using data from two sequencing technologies: the short-read Roche 454 and the long-read Oxford Nanopore MinION sequencers. We sequenced 18 HHV-1 cell culture-isolated clinical specimens collected from immunocompromised patients undergoing antiviral therapy. The susceptibility of the samples to several antivirals was determined by plaque reduction assay. Hybrid genome assembly resulted in a decrease in the number of contigs in 6 out of 7 samples and an increase in N(G)50 and N(G)75 of all 7 samples sequenced by both technologies. The approach also enhanced the detection of non-canonical contigs including a rearrangement between the unique (UL) and repeat (T/IRL) sequence regions of one sample that was not detectable by assembly of 454 reads alone. We detected several known and novel resistance-associated mutations in UL23 and UL30 genes. Genome-wide genetic variability ranged from genomes will be useful in determining genetic determinants of drug resistance, virulence, pathogenesis and viral evolution. The numerous, complex repeat regions of the HHV-1 genome currently remain a barrier towards this goal.

Application of ultra-sons to on-site spent fuel assemblies metrology

International Nuclear Information System (INIS)

Gondard, C.; Saglio, R.; Vouillot, M.; Delaroche, P.; Vaubert, Y.; Van Craeynest, J.C.

1983-12-01

Fuel assemblies inspection on the site of a power reactor, between two irradiation campaigns, allows to estimate the behaviour of prototype fuel assemblies and to permit their refueling for the continuation of the irradiation; the utilization of non-destructive, reliable and high-performance techniques, is of a great interest in the application. For, this reason, the C.E.A. has been led to carry out new techniques allowing the visual examination and the dimensional inspection of spent fuel assemblies of 900 MWe French pressurized water reactors, with a transportable Fuel Examination Module (MEC) on every reactor site. This module includes a television camera, and uses for the first time as ''position sensor'' the properties offered by a set of ultrasonic transducers. The main principle of the design, of the operation way of the module, of the measuring methods, and, of the data acquisition and processing, are presented [fr

Human Assisted Assembly Processes

Energy Technology Data Exchange (ETDEWEB)

CALTON,TERRI L.; PETERS,RALPH R.

2000-01-01

Automatic assembly sequencing and visualization tools are valuable in determining the best assembly sequences, but without Human Factors and Figure Models (HFFMs) it is difficult to evaluate or visualize human interaction. In industry, accelerating technological advances and shorter market windows have forced companies to turn to an agile manufacturing paradigm. This trend has promoted computerized automation of product design and manufacturing processes, such as automated assembly planning. However, all automated assembly planning software tools assume that the individual components fly into their assembled configuration and generate what appear to be a perfectly valid operations, but in reality the operations cannot physically be carried out by a human. Similarly, human figure modeling algorithms may indicate that assembly operations are not feasible and consequently force design modifications; however, if they had the capability to quickly generate alternative assembly sequences, they might have identified a feasible solution. To solve this problem HFFMs must be integrated with automated assembly planning to allow engineers to verify that assembly operations are possible and to see ways to make the designs even better. Factories will very likely put humans and robots together in cooperative environments to meet the demands for customized products, for purposes including robotic and automated assembly. For robots to work harmoniously within an integrated environment with humans the robots must have cooperative operational skills. For example, in a human only environment, humans may tolerate collisions with one another if they did not cause much pain. This level of tolerance may or may not apply to robot-human environments. Humans expect that robots will be able to operate and navigate in their environments without collisions or interference. The ability to accomplish this is linked to the sensing capabilities available. Current work in the field of cooperative

Water-soluble light-emitting nanoparticles prepared by non-covalent bond self-assembly of a hydroxyl group functionalized oligo(p-phenyleneethynylene) with different water-soluble polymers

Institute of Scientific and Technical Information of China (English)

无

2010-01-01

Water-soluble light-emitting nanoparticles were prepared from hydroxyl group functionalized oligos(p-phenyleneethynylene) (OHOPEL) and water-soluble polymers(PEG,PAA,and PG) by non-covalent bond self-assembly.Their structure and optoelectronic properties were investigated through dynamic light scattering(DLS) ,UV and PL spectroscopy.The optical properties of OHOPEL-based water-soluble nanoparticles exhibited the same properties as that found in OHOPEL films,indicating the existence of interchain-aggregation of OHOPELs in the nanoparticles.OHOPEL-based nanoparticles prepared from conjugated oligomers show smaller size and lower dispersity than nanoparticles from conjugated polymers,which means that the structures of water-soluble nanoparticles are linked to the conjugated length.Furthermore,the OHOPEL/PG and OHOPEL/PAA systems produced smaller particles and lower polydispersity than the OHOPEL/PEG system,indicating that there may exist influence of the strength of non-covalent bonds on the size and degree of dispersity of the nanoparticles.

Measurements of time dependent energy spectra of neutrons in a small graphite assembly

International Nuclear Information System (INIS)

Fujita, Yoshiaki; Sakamoto, Shigeyasu; Aizawa, Otohiko; Takahashi, Akito; Sumita, Kenji.

1975-01-01

The time-dependent energy spectra of neutrons have been measured in a small 30x30x30 cm 3 graphite assembly by means of the linac-chopper method, with a view to establishing experimental evidence that there is no asymptotic spectrum in such a small assembly, and in order to study the non-asymptotic behavior of neutrons. The arrangement of a polyethylene pre-moderator adjacent to the assembly made the measurements possible with the improvement obtained thereby of the neutron counting statistics. It was indicated from calculation that the presence of the pre-moderator had little effect - at least above the Bragg cut-off energy - on the evolution in time of the energy spectra of neutrons in the graphite assembly. The experimental results indicated very probable disappearance of asymptotic spectra, and revealed significant enhancement of trapping at Bragg energies with the lapse of time. This is consistent with the results of pulsed neutron experiments in small assemblies conducted by Takahashi et al., and falls in line with de Saussure's approximation. The spectra in the graphite assembly showed significant space dependence, the spectra becoming harder with increasing distance from the pre-moderator. This hardening may be attributed to the relatively faster propagation of higher energy neutrons. (auth.)

A one-pot strategy for biomimetic synthesis and self-assembly of gold nanoparticles

International Nuclear Information System (INIS)

Wang Yi; Li Yuanfang; Zhao Xijuan; Huang Chengzhi; Chen Liqiang; Peng Li

2010-01-01

A simple, one-pot and controllable strategy is reported in this contribution for biomimetic synthesis and self-assembly of gold nanoparticles (Au-NPs). It involves our synthesized polyaldehyde dextran (PAD), which has been proved to be a biomacromolecule with excellent biocompatibility and biodegradability, acting as both a reducing agent and a stabilizer. The morphology of the as-prepared Au-NP assemblies can be controlled by adjusting the reaction conditions, such as the concentration of aldehyde in PAD, the reaction time and the temperature. Investigations of the mechanism suggest that stabilizers may distribute on different crystal facets of NPs non-uniformly owing to the different binding forces, and dipole-dipole interaction of NPs could be the main driving force for the assembly of Au-NPs. In addition, intermolecular hydrogen bonding interaction of stabilizers could also act as a possible driving force. The excellent biocompatibility of the Au-NP assemblies makes them promising candidates for fabricating future optical nanodevices and application in biological systems.

A one-pot strategy for biomimetic synthesis and self-assembly of gold nanoparticles

Science.gov (United States)

Wang, Yi; Chen, Li Qiang; Li, Yuan Fang; Zhao, Xi Juan; Peng, Li; Zhi Huang, Cheng

2010-07-01

A simple, one-pot and controllable strategy is reported in this contribution for biomimetic synthesis and self-assembly of gold nanoparticles (Au-NPs). It involves our synthesized polyaldehyde dextran (PAD), which has been proved to be a biomacromolecule with excellent biocompatibility and biodegradability, acting as both a reducing agent and a stabilizer. The morphology of the as-prepared Au-NP assemblies can be controlled by adjusting the reaction conditions, such as the concentration of aldehyde in PAD, the reaction time and the temperature. Investigations of the mechanism suggest that stabilizers may distribute on different crystal facets of NPs non-uniformly owing to the different binding forces, and dipole-dipole interaction of NPs could be the main driving force for the assembly of Au-NPs. In addition, intermolecular hydrogen bonding interaction of stabilizers could also act as a possible driving force. The excellent biocompatibility of the Au-NP assemblies makes them promising candidates for fabricating future optical nanodevices and application in biological systems.

Self-Assembly of Infinite Structures

Directory of Open Access Journals (Sweden)

Scott M. Summers

2009-06-01

Full Text Available We review some recent results related to the self-assembly of infinite structures in the Tile Assembly Model. These results include impossibility results, as well as novel tile assembly systems in which shapes and patterns that represent various notions of computation self-assemble. Several open questions are also presented and motivated.

Nuclear fuel assembly

International Nuclear Information System (INIS)

Anthony, A.J.

1980-01-01

A bimetallic spacer means is cooperatively associated with a nuclear fuel assembly and operative to resist the occurrence of in-reactor bowing of the nuclear fuel assembly. The bimetallic spacer means in one embodiment of the invention includes a space grid formed, at least principally, of zircaloy to the external surface of which are attached a plurality of stainless steel strips. In another embodiment the strips are attached to fuel pins. In each of the embodiments, the stainless steel strips during power production expand outwardly to a greater extent than do the members to which the stainless steel strips are attached, thereby forming stiff springs which abut against like bimetallic spacer means with which the other nuclear fuel assemblies are provided in a given nuclear reactor core to thus prevent the occurrence of in-reactor bowing of the nuclear fuel assemblies. (author)

Nuclear fuel assembly

International Nuclear Information System (INIS)

Betten, P.R.

1976-01-01

Under the invention the fuel assembly is particularly suitable for liquid metal cooled fast neutron breeder reactors. Hence, according to the invention a fuel assembly cladding includes inward corrugations with respect to the remainder of the cladding according to a recurring pattern determined by the pitch of the metal wire helically wound round the fuel rods of the assembly. The parts of the cladding pressed inwards correspond to the areas in which the wire encircling the peripheral fuel rods is generally located apart from the cladding, thereby reducing the play between the cladding and the peripheral fuel rods situated in these areas. The reduction in the play in turn improves the coolant flow in the internal secondary channels of the fuel assembly to the detriment of the flow in the peripheral secondary channels and thereby establishes a better coolant fluid temperature profile [fr

Method and apparatus for assembling a permanent magnet pole assembly

Science.gov (United States)

Carl, Jr., Ralph James; Bagepalli, Bharat Sampathkumaran [Niskayuna, NY; Jansen, Patrick Lee [Scotia, NY; Dawson, Richard Nils [Voorheesville, NY; Qu, Ronghai [Clifton Park, NY; Avanesov, Mikhail Avramovich [Moscow, RU

2009-08-11

A pole assembly for a rotor, the pole assembly includes a permanent magnet pole including at least one permanent magnet block, a plurality of laminations including a pole cap mechanically coupled to the pole, and a plurality of laminations including a base plate mechanically coupled to the pole.

TPX assembly plan

International Nuclear Information System (INIS)

Knutson, D.

1993-01-01

The TPX machine will be assembled in the TFTR Test Cell at the Plasma Physics Laboratory, utilizing the existing TFTR machine foundation. Preparation of the area for assembly will begin after completion of the decontamination and decommissioning phase on TFTR and certification that the radiation levels remaining, if any, are consistent with the types of operations planned. Assembly operations begin with the arrival of the first components, and conclude, approximately 24 months later, with the successful completion of the integrated systems tests and the achievement of a first plasma

Modular assembly of chimeric phi29 packaging RNAs that support DNA packaging.

Science.gov (United States)

Fang, Yun; Shu, Dan; Xiao, Feng; Guo, Peixuan; Qin, Peter Z

2008-08-08

The bacteriophage phi29 DNA packaging motor is a protein/RNA complex that can produce strong force to condense the linear-double-stranded DNA genome into a pre-formed protein capsid. The RNA component, called the packaging RNA (pRNA), utilizes magnesium-dependent inter-molecular base-pairing interactions to form ring-shaped complexes. The pRNA is a class of non-coding RNA, interacting with phi29 motor proteins to enable DNA packaging. Here, we report a two-piece chimeric pRNA construct that is fully competent in interacting with partner pRNA to form ring-shaped complexes, in packaging DNA via the motor, and in assembling infectious phi29 virions in vitro. This is the first example of a fully functional pRNA assembled using two non-covalently interacting fragments. The results support the notion of modular pRNA architecture in the phi29 packaging motor.

Nondestructive determination of burnup and fissile isotope balance in spent fuel assemblies of water cooled reactors

International Nuclear Information System (INIS)

Pinel, J.

1983-03-01

Two non-destructive methods for measuring fuel assemblies in storage pools have been developed: a gamma fuel scanning method, using the 134 Cs - 137 Cs and 144 Ce gamma rays, and the measurement of the neutron flux emitted by the fuel assembly. For interpreting the measurement, we have used calculated correlations to establish a connection between the measured phenomena and the parameters to be determined. A measurement campaign involving 58 assemblies from the C.N.A. reactor was conducted in the reprocessing plant of LA HAGUE. The results obtained show that the objectives can be achevied within an industrial environment [fr

Assembly Modulated by Particle Position and Shape: A New Concept in Self-Assembly

DEFF Research Database (Denmark)

Tavacoli, Joe W; Heuvingh, Julien; Du Roure, Olivia

2017-01-01

In this communication we outline how the bespoke arrangements and design of micron-sized superparamagnetic shapes provide levers to modulate their assembly under homogeneous magnetic fields. We label this new approach, 'assembly modulated by particle position and shape' (APPS). Specifically, using...... rectangular lattices of superparamagnetic micron-sized cuboids, we construct distinct microstructures by adjusting lattice pitch and angle of array with respect to a magnetic field. Broadly, we find two modes of assembly: (1) immediate 2D jamming of the cuboids as they rotate to align with the applied field...... (rotation-induced jamming) and (2) aggregation via translation after their full alignment (dipole-dipole assembly). The boundary between these two assembly pathways is independent on field strength being solely a function of the cuboid's dimensions, lattice pitch, and array angle with respect to field...

Design of polymer motifs for nucleic acid recognition and assembly stabilization

Science.gov (United States)

Zhou, Zhun

This dissertation describes the synthesis and assembly of bio-functional polymers and the applications of these polymers to drug encapsulation, delivery, and multivalent biomimetic macromolecular recognition between synthetic polymer and nucleic acids. The main content is divided into three parts: (1) polyacidic domains as strongly stabilizing design elements for aqueous phase polyacrylate diblock assembly; (2) small molecule/polymer recognition triggered macromolecular assembly and drug encapsulation; (3) trizaine derivatized polymer as a novel class of "bifacial polymer nucleic acid" (bPoNA) and applications of bPoNA to nanoparticle loading of DNA/RNA, silencing delivery as well as control of aptamer function. Through the studies in part (1) and part (2), it was demonstrated that well-designed polymer motifs are not only able to enhance assemblies driven by non-specific hydrophobic effect, but are also able to direct assemblies based on specific recognitions. In part (3) of this dissertation, this concept was further extended by the design of polyacrylate polymers that are capable of discrete and robust hybridization with nucleic acids. This surprising finding demonstrated both fundamental and practical applications. Overall, these studies provided insights into the rational design elements for improving the bio-functions of synthetic polymers, and significantly expanded the scope of biological applications in which polymers synthesized via controlled radical polymerization may play a role.

Dynamic behaviour of diagnostic assemblies

International Nuclear Information System (INIS)

Pecinka, L.

1980-01-01

The methodology is shown of calculating the frequency spectrum of a diagnostic assembly. The oscillations of the assembly as a whole, of a fuel rod bundle, the assembly jacket and of the individual rods in the bundle were considered. The manufacture is suggested of a model assembly which would be used for testing forced vibrations using an experimental water loop. (M.S.)

Selecting Operations for Assembler Encoding

Directory of Open Access Journals (Sweden)

Tomasz Praczyk

2010-04-01

Full Text Available Assembler Encoding is a neuro-evolutionary method in which a neural network is represented in the form of a simple program called Assembler Encoding Program. The task of the program is to create the so-called Network Definition Matrix which maintains all the information necessary to construct the network. To generate Assembler Encoding Programs and the subsequent neural networks evolutionary techniques are used.
The performance of Assembler Encoding strongly depends on operations used in Assembler Encoding Programs. To select the most effective operations, experiments in the optimization and the predator-prey problem were carried out. In the experiments, Assembler Encoding Programs equipped with different types of operations were tested. The results of the tests are presented at the end of the paper.

Flashback resistant pre-mixer assembly

Science.gov (United States)

Laster, Walter R [Oviedo, FL; Gambacorta, Domenico [Oviedo, FL

2012-02-14

A pre-mixer assembly associated with a fuel supply system for mixing of air and fuel upstream from a main combustion zone in a gas turbine engine. The pre-mixer assembly includes a swirler assembly disposed about a fuel injector of the fuel supply system and a pre-mixer transition member. The swirler assembly includes a forward end defining an air inlet and an opposed aft end. The pre-mixer transition member has a forward end affixed to the aft end of the swirler assembly and an opposed aft end defining an outlet of the pre-mixer assembly. The aft end of the pre-mixer transition member is spaced from a base plate such that a gap is formed between the aft end of the pre-mixer transition member and the base plate for permitting a flow of purge air therethrough to increase a velocity of the air/fuel mixture exiting the pre-mixer assembly.

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Sasaki, Y.; Tashima, J.

1975-01-01

A description is given of nuclear reactor fuel assemblies arranged in the form of a lattice wherein there is attached to the interface of one of two adjacent fuel assemblies a plate spring having a concave portion curved toward said interface and to the interface of the other fuel assembly a plate spring having a convex portion curved away from said interface

Design of the ITER Tokamak Assembly Tools

International Nuclear Information System (INIS)

Park, Hyunki; Her, Namil; Kim, Byungchul; Im, Kihak; Jung, Kijung; Lee, Jaehyuk; Im, Kisuk

2006-01-01

ITER (International Thermonuclear Experimental Reactor) Procurement allocation among the seven Parties, EU, JA, CN, IN , KO, RF and US had been decided in Dec. 2005. ITER Tokamak assembly tools is one of the nine components allocated to Korea for the construction of the ITER. Assembly tools except measurement and common tools are supplied to assemble the ITER Tokamak and classified into 9 groups according to components to be assembled. Among the 9 groups of assembly tools, large-sized Sector Sub-assembly Tools and Sector Assembly Tools are used at the first stage of ITER Tokamak construction and need to be designed faster than seven other assembly tools. ITER IT (International Team) proposed Korea to accomplish ITA (ITER Transitional Arrangements) Task on detailed design, manufacturing feasibility and contract specification of specific, large sized tools such as Upending Tool, Lifting Tool, Sector Sub-assembly Tool and Sector Assembly Tool in Oct. 2004. Based on the concept design by ITER IT, Korea carried out ITA Task on detailed design of large-sized and specific Sector Sub-assembly and Sector Assembly Tools until Mar. 2006. The Sector Sub-assembly Tools mainly consist of the Upending, Lifting, Vacuum Vessel Support and Bracing, and Sector Sub-assembly Tool, among which the design of three tools are herein. The Sector Assembly Tools mainly consist of the Toroidal Field (TF) Gravity Support Assembly, Sector In-pit Assembly, TF Coil Assembly, Vacuum Vessel (VV) Welding and Vacuum Vessel Thermal Shield (TS) Assembly Tool, among which the design of Sector In-pit Assembly Tool is described herein

Judgement on the data for fuel assembly outlet temperatures of WWER fuel assemblies in power reactors based on measurements with experimental fuel assemblies

International Nuclear Information System (INIS)

Krause, F.

1986-01-01

In the period from 1980 to 1985, in the Rheinsberg nuclear power plant experimental fuel assemblies were used on lattices at the periphery of the core. These particular fuel assemblies dispose of an extensive in-core instrumentation with different sensors. Besides this, they are fit out with a device to systematically thottle the coolant flow. The large power gradient present at the core position of the experimental fuel assembly causes a temperature profile along the fuel assemblies which is well provable at the measuring points of the outlet temperature. Along the direction of flow this temperature profile in the coolant degrades only slowly. This effect is to be taken into account when measuring the fuel assembly outlet temperature of WWER fuel assemblies. Besides this, the results of the measurements hinted both at a γ-heating of the temperature measuring points and at tolerances in the calculation of the micro power density distribution. (author)

Fuel assemblies

International Nuclear Information System (INIS)

Nagano, Mamoru; Yoshioka, Ritsuo

1983-01-01

Purpose: To effectively utilize nuclear fuels by increasing the reactivity of a fuel assembly and reduce the concentration at the central region thereof upon completion of the burning. Constitution: A fuel assembly is bisected into a central region and a peripheral region by disposing an inner channel box within a channel box. The flow rate of coolants passing through the central region is made greater than that in the peripheral region. The concentration of uranium 235 of the fuel rods in the central region is made higher. In such a structure, since the moderating effect in the central region is improved, the reactivity of the fuel assembly is increased and the uranium concentration in the central region upon completion of the burning can be reduced, fuel economy and effective utilization of uranium can be attained. (Kamimura, M.)

Fuel assembly

International Nuclear Information System (INIS)

Nakatsuka, Masafumi; Matsuzuka, Ryuji.

1976-01-01

Object: To provide a fuel assembly which can decrease pressure loss of coolant to uniform temperature. Structure: A sectional area of a flow passage in the vicinity of an inner peripheral surface of a wrapper tube is limited over the entire length to prevent the temperature of a fuel element in the outermost peripheral portion from being excessively decreased to thereby flatten temperature distribution. To this end, a plurality of pincture-frame-like sheet metals constituting a spacer for supporting a fuel assembly, which has a plurality of fuel elements planted lengthwise and in given spaced relation within the wrapper tube, is disposed in longitudinal grooves and in stacked fashion to form a substantially honeycomb-like space in cross section. The fuel elements are inserted and supported in the space to form a fuel assembly. (Kamimura, M.)

Welding facilities for NPP assembling

International Nuclear Information System (INIS)

Rojtenberg, S.S.

1987-01-01

Recommendations concerning the choice of equipment for welding in pre-assembling work shops, in the enlarging assembling shops and at the assembling site, are given. Advanced production automatic welders and semiautomatic machines, applied during the NPP equipment assembling as well as automatic machines specially produced for welding the main reactor components and pipelines are described. Automatic and semiautomatic machine and manual welding post supply sources are considered

Controlled short-linkage assembly of functional nano-objects

Energy Technology Data Exchange (ETDEWEB)

Chaudhary, Shilpi; Kamra, Tripta [Division of Pure and Applied Biochemistry, Lund University, Box 124, 221 00 Lund (Sweden); ENI AB, Malmö (Sweden); Division of Synchrotron Radiation Research, Lund University, Box 118, 221 00 Lund (Sweden); Uddin, Khan Mohammad Ahsan [Division of Pure and Applied Biochemistry, Lund University, Box 124, 221 00 Lund (Sweden); Snezhkova, Olesia [Division of Synchrotron Radiation Research, Lund University, Box 118, 221 00 Lund (Sweden); Jayawardena, H. Surangi N. [Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854 (United States); Yan, Mingdi [Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854 (United States); Department of Chemistry, KTH – Royal Institute of Technology, Teknikringen 30, S-10044 Stockholm (Sweden); Montelius, Lars [ENI AB, Malmö (Sweden); Schnadt, Joachim, E-mail: joachim.schnadt@sljus.lu.se [Division of Synchrotron Radiation Research, Lund University, Box 118, 221 00 Lund (Sweden); Ye, Lei, E-mail: lei.ye@tbiokem.lth.se [Division of Pure and Applied Biochemistry, Lund University, Box 124, 221 00 Lund (Sweden)

2014-05-01

Graphical abstract: - Highlights: • Fast photoconjugation of nanoparticles on surface. • Non-destructive feature guarantees intact function of nanoparticles. • Direct contact between nano-objects allows efficient photon and electron transfer. • Possibility of generating patterned nanoparticle assemblies on surface. • Open new opportunities for assembling chemical sensors. - Abstract: In this work, we report a method that allows the deterministic, photo-controlled covalent assembly of nanoparticles directly on surface. As a model system, we study the conjugation of molecularly imprinted polymer (MIP) nanoparticles on a glass surface and confirm that the immobilized nanoparticles maintain their molecular recognition functionality. The glass slide was first modified with perfluorophenylazide and then used to bind MIP nanoparticles under UV irradiation. After each step the surface was analyzed by water contact angle measurement, fluorescence microscopy, scanning electron microscopy, and/or synchrotron-based X-ray photoelectron spectroscopy. The MIP nanoparticles immobilized on the glass surface remained stable and maintained specific binding for the template molecule, propranolol. The method developed in this work allows MIP nanoparticles to be directly coupled to a flat surface, offering a straightforward means to construct robust chemical sensors. Using the reported photo conjugation method, it is possible to generate patterned assembly of nanoparticles using a photomask. Since perfluorophenylazide-based photochemistry works with all kinds of organic material, the method developed in this work is expected to enable immobilization of not only MIPs but also other kinds of organic and inorganic–organic core–shell particles for various applications involving photon or electron transfer.

Controlled short-linkage assembly of functional nano-objects

International Nuclear Information System (INIS)

Chaudhary, Shilpi; Kamra, Tripta; Uddin, Khan Mohammad Ahsan; Snezhkova, Olesia; Jayawardena, H. Surangi N.; Yan, Mingdi; Montelius, Lars; Schnadt, Joachim; Ye, Lei

2014-01-01

Graphical abstract: - Highlights: • Fast photoconjugation of nanoparticles on surface. • Non-destructive feature guarantees intact function of nanoparticles. • Direct contact between nano-objects allows efficient photon and electron transfer. • Possibility of generating patterned nanoparticle assemblies on surface. • Open new opportunities for assembling chemical sensors. - Abstract: In this work, we report a method that allows the deterministic, photo-controlled covalent assembly of nanoparticles directly on surface. As a model system, we study the conjugation of molecularly imprinted polymer (MIP) nanoparticles on a glass surface and confirm that the immobilized nanoparticles maintain their molecular recognition functionality. The glass slide was first modified with perfluorophenylazide and then used to bind MIP nanoparticles under UV irradiation. After each step the surface was analyzed by water contact angle measurement, fluorescence microscopy, scanning electron microscopy, and/or synchrotron-based X-ray photoelectron spectroscopy. The MIP nanoparticles immobilized on the glass surface remained stable and maintained specific binding for the template molecule, propranolol. The method developed in this work allows MIP nanoparticles to be directly coupled to a flat surface, offering a straightforward means to construct robust chemical sensors. Using the reported photo conjugation method, it is possible to generate patterned assembly of nanoparticles using a photomask. Since perfluorophenylazide-based photochemistry works with all kinds of organic material, the method developed in this work is expected to enable immobilization of not only MIPs but also other kinds of organic and inorganic–organic core–shell particles for various applications involving photon or electron transfer

Composite turbine bucket assembly

Science.gov (United States)

Liotta, Gary Charles; Garcia-Crespo, Andres

2014-05-20

A composite turbine blade assembly includes a ceramic blade including an airfoil portion, a shank portion and an attachment portion; and a transition assembly adapted to attach the ceramic blade to a turbine disk or rotor, the transition assembly including first and second transition components clamped together, trapping said ceramic airfoil therebetween. Interior surfaces of the first and second transition portions are formed to mate with the shank portion and the attachment portion of the ceramic blade, and exterior surfaces of said first and second transition components are formed to include an attachment feature enabling the transition assembly to be attached to the turbine rotor or disk.

Analysis Of Transcriptomes In A Porcine Tissue Collection Using RNA-Seq And Genome Assembly 10

DEFF Research Database (Denmark)

Hornshøj, Henrik; Thomsen, Bo; Hedegaard, Jakob

2011-01-01

The release of Sus scrofa genome assembly 10 supports improvement of the pig genome annotation and in depth transcriptome analyses using next-generation sequencing technologies. In this study we analyze RNA-seq reads from a tissue collection, including 10 separate tissues from Duroc boars and 10...... short read alignment software we mapped the reads to the genome assembly 10. We extracted contig sequences of gene transcripts using the Cufflinks software. Based on this information we identified expressed genes that are present in the genome assembly. The portion of these genes being previously known...... was roughly estimated by sequence comparison to known genes. Similarly, we searched for genes that are expressed in the tissues but not present in the genome assembly by aligning the non-genome-mapped reads to known gene transcripts. For the genes predicted to have alternative transcript variants by Cufflinks...

TOOL ASSEMBLY WITH BI-DIRECTIONAL BEARING

Science.gov (United States)

Longhurst, G.E.

1961-07-11

A two-direction motion bearing which is incorporated in a refueling nuclear fuel element trsnsfer tool assembly is described. A plurality of bi- directional bearing assembliesare fixed equi-distantly about the circumference of the transfer tool assembly to provide the tool assembly with a bearing surface- for both axial and rotational motion. Each bi-directional bearing assembly contains a plurality of circumferentially bulged rollers mounted in a unique arrangement which will provide a bearing surface for rotational movement of the tool assembly within a bore. The bi-direc tional bearing assembly itself is capable of rational motion and thus provides for longitudinal movement of the tool assembly.

Tritium breeding experiments in a fusion blanket assembly using a low-intensity neutron generator

International Nuclear Information System (INIS)

Dalton, A.W.; Woodley, H.J.; McGregor, B.J.

1987-01-01

Experiments have been carried out to determine the accuracy with which tritium production rates (TPRs) can be measured in a fusion blanket assembly of non-spherical geometry by a non-central low intensity D-T neutron source (2x10 10 neutrons per second). The tritium production was determined for samples of lithium carbonate containing high enrichments of 6 Li(96%) and 7 Li(99.9%). The measured data were used to check the accuracy with which the TPRs could be numerically predicted using current nuclear data and calculational methods. The numerical predictions from tritium production from the 7 Li samples agreed within the experimental errors of the measurements, but 6 Li measurements which differ by more than 20 per cent from the predicted values were observed in the lower half of the assembly

Fuel assembly spacer

International Nuclear Information System (INIS)

Shirakawa, Ken-etsu.

1988-01-01

Purpose: To reduce the pressure loss of coolants by fuel assembly spacers. Constitution: Spacers for supporting a fuel assembly are attached by means of a plurality of wires to an outer frame. The outer frame is made of shape memory alloy such that the wires are caused to slacken at normal temperature and the slacking of the wires is eliminated in excess of the transition temperature. Since the wires slacken at the normal temperature, fuel rods can be inserted easily. After the insertion of the fuel rods, when the entire portion or the outer frame is heated by water or gas at a predetermined temperature, the outer frame resumes its previously memorized shape to tighten the wires and, accordingly, the fuel rods can be supported firmly. In this way, since the fuel rods are inserted in the slacken state of the wires and, after the assembling, the outer frame resumes its memorized shape, the assembling work can be conducted efficiently. (Kamimura, M.)

Ordinary General Assembly

CERN Multimedia

Staff Association

2011-01-01

Tuesday 12 April at 14.00 Council Chamber, Bldg 503 In conformity with the Statutes of the Staff Association, an ordinary General Assembly is organized once a year (article IV.2.1). Agenda   Adoption of the Agenda Approval of the Draft Minutes of the Ordinary General Assembly of 20 April 2010 Presentation and approval of the Activity Report 2010 Presentation and approval of the Financial Report 2010 Presentation and approval of the Auditors Report 2010 Programme for 2011 Presentation et and approval of the draft budget and subscription rate 2012 Election of the Election Committee Election of the Board of Auditors Miscellaneous We remind members of article IV.3.4 in the Statutes of the Association which reads: “After having dealt with all the items on the agenda, the members may, with the consent of the Assembly, have other matters discussed, but decisions may be taken only on the items listed on the agenda. Nevertheless, the Assembly ma...

Ordinary General Assembly

CERN Multimedia

Staff Association

2011-01-01

Tuesday 12 April at 14.00 Council Chamber, Bldg 503 In conformity with the Statutes of the Staff Association, an ordinary General Assembly is organized once a year (article IV.2.1). Agenda   Adoption of the Agenda Approval of the Draft Minutes of the Ordinary General Assembly of 20 April 2010 Presentation and approval of the Activity Report 2010 Presentation and approval of the Financial Report 2010 Presentation and approval of the Auditors Report 2010 Programme for 2011 Presentation and approval of the draft budget and subscription rate 2012 Election of the Election Committee Election of the Board of Auditors Miscellaneous We remind members of article IV.3.4 in the Statutes of the Association which reads: “After having dealt with all the items on the agenda, the members may, with the consent of the Assembly, have other matters discussed, but decisions may be taken only on the items listed on the agenda. Nevertheless, the Assembly may r...

Ordinary General Assembly

CERN Multimedia

Staff Association

2010-01-01

Tuesday 20 April at 10.00 Council Chamber, Bldg 503 In conformity with the Statutes of the Staff Association, an ordinary General Assembly is organized once a year (article IV.2.1). Agenda   Adoption of the Agenda Approval of the Draft Minutes of the Ordinary General Assembly of 12 May 2009 Presentation and approval of the Activity Report 2009 Presentation and approval of the Financial Report 2009 Presentation and approval of the Auditors Report 2009 Programme for 2010 Presentation et and approval of the draft budget and subscription rate 2010 Election of the Election Committee Election of the Board of Auditors Miscellaneous We remind members of article IV.3.4 in the Statutes of the Association which reads: “After having dealt with all the items on the agenda, the members may, with the consent of the Assembly, have other matters discussed, but decisions may be taken only on the items listed on the agenda. Nevertheless, the Assembly may require t...

Preliminary High-Throughput Metagenome Assembly

Energy Technology Data Exchange (ETDEWEB)

Dusheyko, Serge; Furman, Craig; Pangilinan, Jasmyn; Shapiro, Harris; Tu, Hank

2007-03-26

Metagenome data sets present a qualitatively different assembly problem than traditional single-organism whole-genome shotgun (WGS) assembly. The unique aspects of such projects include the presence of a potentially large number of distinct organisms and their representation in the data set at widely different fractions. In addition, multiple closely related strains could be present, which would be difficult to assemble separately. Failure to take these issues into account can result in poor assemblies that either jumble together different strains or which fail to yield useful results. The DOE Joint Genome Institute has sequenced a number of metagenomic projects and plans to considerably increase this number in the coming year. As a result, the JGI has a need for high-throughput tools and techniques for handling metagenome projects. We present the techniques developed to handle metagenome assemblies in a high-throughput environment. This includes a streamlined assembly wrapper, based on the JGI?s in-house WGS assembler, Jazz. It also includes the selection of sensible defaults targeted for metagenome data sets, as well as quality control automation for cleaning up the raw results. While analysis is ongoing, we will discuss preliminary assessments of the quality of the assembly results (http://fames.jgi-psf.org).

Assembling Transgender Moments

Science.gov (United States)

Greteman, Adam J.

2017-01-01

In this article, the author seeks to assemble moments--scholarly, popular, and aesthetic--in order to explore the possibilities that emerge as moments collect in education's encounters with the needs, struggles, and possibilities of transgender lives and practices. Assembling moments, the author argues, illustrates the value of "moments"…

Centrioles: some self-assembly required.

Science.gov (United States)

Song, Mi Hye; Miliaras, Nicholas B; Peel, Nina; O'Connell, Kevin F

2008-12-01

Centrioles play an important role in organizing microtubules and are precisely duplicated once per cell cycle. New (daughter) centrioles typically arise in association with existing (mother) centrioles (canonical assembly), suggesting that mother centrioles direct the formation of daughter centrioles. However, under certain circumstances, centrioles can also selfassemble free of an existing centriole (de novo assembly). Recent work indicates that the canonical and de novo pathways utilize a common mechanism and that a mother centriole spatially constrains the self-assembly process to occur within its immediate vicinity. Other recently identified mechanisms further regulate canonical assembly so that during each cell cycle, one and only one daughter centriole is assembled per mother centriole.

Fuel assembly storage pool

International Nuclear Information System (INIS)

Hiranuma, Hiroshi.

1976-01-01

Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

Membranes Prepared by Self-assembly and Chelation Assisted Phase Inversion

KAUST Repository

Xie, Yihui; Sutisna, Burhannudin; Nunes, Suzana Pereira

2017-01-01

We combine self-assembly in solution, complexation with metallic salts and phase separation induced by solvent-non-solvent exchange to prepare nanostructured membranes for separation in the nanofiltration range. The method was applied to synthesized poly(acrylic acid)-b-polysulfone-b-poly(acrylic acid) copolymers dissolved in a selective solvent mixture and immersed in aqueous Cu2+ or Ag+ solutions.

Membranes Prepared by Self-assembly and Chelation Assisted Phase Inversion

KAUST Repository

Xie, Yihui

2017-05-19

We combine self-assembly in solution, complexation with metallic salts and phase separation induced by solvent-non-solvent exchange to prepare nanostructured membranes for separation in the nanofiltration range. The method was applied to synthesized poly(acrylic acid)-b-polysulfone-b-poly(acrylic acid) copolymers dissolved in a selective solvent mixture and immersed in aqueous Cu2+ or Ag+ solutions.

Polymer Directed Protein Assemblies

Directory of Open Access Journals (Sweden)

Patrick van Rijn

2013-05-01

Full Text Available Protein aggregation and protein self-assembly is an important occurrence in natural systems, and is in some form or other dictated by biopolymers. Very obvious influences of biopolymers on protein assemblies are, e.g., virus particles. Viruses are a multi-protein assembly of which the morphology is dictated by poly-nucleotides namely RNA or DNA. This “biopolymer” directs the proteins and imposes limitations on the structure like the length or diameter of the particle. Not only do these bionanoparticles use polymer-directed self-assembly, also processes like amyloid formation are in a way a result of directed protein assembly by partial unfolded/misfolded biopolymers namely, polypeptides. The combination of proteins and synthetic polymers, inspired by the natural processes, are therefore regarded as a highly promising area of research. Directed protein assembly is versatile with respect to the possible interactions which brings together the protein and polymer, e.g., electrostatic, v.d. Waals forces or covalent conjugation, and possible combinations are numerous due to the large amounts of different polymers and proteins available. The protein-polymer interacting behavior and overall morphology is envisioned to aid in clarifying protein-protein interactions and are thought to entail some interesting new functions and properties which will ultimately lead to novel bio-hybrid materials.

Regulation of nucleolus assembly by non-coding RNA polymerase II transcripts.

Science.gov (United States)

Caudron-Herger, Maïwen; Pankert, Teresa; Rippe, Karsten

2016-05-03

The nucleolus is a nuclear subcompartment for tightly regulated rRNA production and ribosome subunit biogenesis. It also acts as a cellular stress sensor and can release enriched factors in response to cellular stimuli. Accordingly, the content and structure of the nucleolus change dynamically, which is particularly evident during cell cycle progression: the nucleolus completely disassembles during mitosis and reassembles in interphase. Although the mechanisms that drive nucleolar (re)organization have been the subject of a number of studies, they are only partly understood. Recently, we identified Alu element-containing RNA polymerase II transcripts (aluRNAs) as important for nucleolar structure and rRNA synthesis. Integrating these findings with studies on the liquid droplet-like nature of the nucleolus leads us to propose a model on how RNA polymerase II transcripts could regulate the assembly of the nucleolus in response to external stimuli and during cell cycle progression.

Multi-scale coarse-graining for the study of assembly pathways in DNA-brick self-assembly

Science.gov (United States)

Fonseca, Pedro; Romano, Flavio; Schreck, John S.; Ouldridge, Thomas E.; Doye, Jonathan P. K.; Louis, Ard A.

2018-04-01

Inspired by recent successes using single-stranded DNA tiles to produce complex structures, we develop a two-step coarse-graining approach that uses detailed thermodynamic calculations with oxDNA, a nucleotide-based model of DNA, to parametrize a coarser kinetic model that can reach the time and length scales needed to study the assembly mechanisms of these structures. We test the model by performing a detailed study of the assembly pathways for a two-dimensional target structure made up of 334 unique strands each of which are 42 nucleotides long. Without adjustable parameters, the model reproduces a critical temperature for the formation of the assembly that is close to the temperature at which assembly first occurs in experiments. Furthermore, the model allows us to investigate in detail the nucleation barriers and the distribution of critical nucleus shapes for the assembly of a single target structure. The assembly intermediates are compact and highly connected (although not maximally so), and classical nucleation theory provides a good fit to the height and shape of the nucleation barrier at temperatures close to where assembly first occurs.

Dynamic Multi-Component Hemiaminal Assembly

Science.gov (United States)

You, Lei; Long, S. Reid; Lynch, Vincent M.

2012-01-01

A simple approach to generating in situ metal templated tris-(2-picolyl)amine-like multi-component assemblies with potential applications in molecular recognition and sensing is reported. The assembly is based on the reversible covalent association between di-(2-picolyl)amine and aldehydes. Zinc ion is the best for inducing assembly among the metal salts investigated, while 2-picolinaldehyde is the best among the heterocyclic aldehydes studied. Although an equilibrium constant of 6.6 * 103 M-1 was measured for the assembly formed by 2-picolinaldehdye, di-(2-picolyl)amine, and zinc triflate, the equilibrium constants for other systems are in the 102 M-1 range. X-ray structural analysis revealed that zinc adopts a trigonal bipyramidal geometry within the assembled ligand. The diversity and equilibrium of the assemblies are readily altered by simply changing concentrations, varying components, or adding counter anions. PMID:21919095

X-ray radiography equipment for patients in standing position

International Nuclear Information System (INIS)

Snijder, J.G.N.

1974-01-01

X-ray radiography equipment suited for patients in standing position is described. The patient's body centre of mass is indicated by its vertical projection line appearing on the X-ray image. To that end, an X-ray absorbing wire is positioned through the centre of mass by means of an electrical signal acting on a servomotor and derived from the pressure on three non-colinear points in the foot plate through an analogue computer

Advanced gray rod control assembly

Science.gov (United States)

Drudy, Keith J; Carlson, William R; Conner, Michael E; Goldenfield, Mark; Hone, Michael J; Long, Jr., Carroll J; Parkinson, Jerod; Pomirleanu, Radu O

2013-09-17

An advanced gray rod control assembly (GRCA) for a nuclear reactor. The GRCA provides controlled insertion of gray rod assemblies into the reactor, thereby controlling the rate of power produced by the reactor and providing reactivity control at full power. Each gray rod assembly includes an elongated tubular member, a primary neutron-absorber disposed within the tubular member said neutron-absorber comprising an absorber material, preferably tungsten, having a 2200 m/s neutron absorption microscopic capture cross-section of from 10 to 30 barns. An internal support tube can be positioned between the primary absorber and the tubular member as a secondary absorber to enhance neutron absorption, absorber depletion, assembly weight, and assembly heat transfer characteristics.

Multi-Robot Assembly Strategies and Metrics

Science.gov (United States)

MARVEL, JEREMY A.; BOSTELMAN, ROGER; FALCO, JOE

2018-01-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies. PMID:29497234

Multi-Robot Assembly Strategies and Metrics.

Science.gov (United States)

Marvel, Jeremy A; Bostelman, Roger; Falco, Joe

2018-02-01

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles. In this survey, we identify the types of assemblies that are enabled by utilizing multiple robots, the algorithms that synchronize the motions of the robots to complete the assembly operations, and the metrics used to assess the quality and performance of the assemblies.

Minimalistic peptide supramolecular co-assembly: expanding the conformational space for nanotechnology.

Science.gov (United States)

Makam, Pandeeswar; Gazit, Ehud

2018-05-21

Molecular self-assembly is a ubiquitous process in nature and central to bottom-up nanotechnology. In particular, the organization of peptide building blocks into ordered supramolecular structures has gained much interest due to the unique properties of the products, including biocompatibility, chemical and structural diversity, robustness and ease of large-scale synthesis. In addition, peptides, as short as dipeptides, contain all the molecular information needed to spontaneously form well-ordered structures at both the nano- and the micro-scale. Therefore, peptide supramolecular assembly has been effectively utilized to produce novel materials with tailored properties for various applications in the fields of material science, engineering, medicine, and biology. To further expand the conformational space of peptide assemblies in terms of structural and functional complexity, multicomponent (two or more) peptide supramolecular co-assembly has recently evolved as a promising extended approach, similar to the structural diversity of natural sequence-defined biopolymers (proteins) as well as of synthetic covalent co-polymers. The use of this methodology was recently demonstrated in various applications, such as nanostructure physical dimension control, the creation of non-canonical complex topologies, mechanical strength modulation, the design of light harvesting soft materials, fabrication of electrically conducting devices, induced fluorescence, enzymatic catalysis and tissue engineering. In light of these significant advancements in the field of peptide supramolecular co-assembly in the last few years, in this tutorial review, we provide an updated overview and future prospects of this emerging subject.

Effect of Dendritic Polymer Architecture on Biological Behaviors of Self-Assembled Nanocarriers

Science.gov (United States)

Hsu, Hao-Jui

Polymeric self-assembled nanocarriers represent one of the most versatile platforms for drug delivery. Through tailoring the physiochemical properties of amphiphilic block copolymers, self-assembled nanocarriers with great thermodynamic stability and desired biological properties could be achieved. The PEGylated dendron-based copolymers (PDCs) are one of the novel amphiphilic copolymers that have attracted a great deal of scientific interest due to their unique dendritic structure and properties. While the dendritic polymer architecture of PDC has been shown to enhance the thermodynamic stability of the self-assembling PDCs, dendron micelles, the effect of this polymer architecture on the biological properties of dendron micelles has not yet been studied. Therefore, this dissertation research is focused on understanding the role of dendritic polymer structure on moderating the biological properties of various self-assembled nanocarriers. To systematically investigate this, three studies have been designed and performed. First, we studied whether the dendritic structure of PDC allows dendron micelles to behave non-specific cellular interactions in a similar way that dendrimers would do. Second, cell-specific interactions of dendron micelles mediated by conjugated ligands were investigated. Third, we investigated the influence of dendritic PEG outer shell on micelle-serum protein interactions and its subsequent implication. Our results revealed that both non-specific and specific cellular interactions of dendron micelles were controllable through modulation of the PEG corona length. While the non-specific charge-dependent cellular interactions of dendron micelles were tunable through controlling the length of PEG corona, the use of long PEG tether was found to enhance the ligand-mediated cellular interactions of dendron micelles. With the ligand tethers, a 27-fold enhancement in ligand-mediated cellular interactions can be achieved, compared to non-targeted dendron

ASSEMBLY TRANSFER SYSTEM DESCRIPTION DOCUMENT

International Nuclear Information System (INIS)

Gorpani, B.

2000-01-01

The Assembly Transfer System (ATS) receives, cools, and opens rail and truck transportation casks from the Carrier/Cask Handling System (CCHS). The system unloads transportation casks consisting of bare Spent Nuclear Fuel (SNF) assemblies, single element canisters, and Dual Purpose Canisters (DPCs). For casks containing DPCs, the system opens the DPCs and unloads the SNF. The system stages the assemblies, transfer assemblies to and from fuel-blending inventory pools, loads them into Disposal Containers (DCs), temporarily seals and inerts the DC, decontaminates the DC and transfers it to the Disposal Container Handling System. The system also prepares empty casks and DPCs for off-site shipment. Two identical Assembly Transfer System lines are provided in the Waste Handling Building (WHB). Each line operates independently to handle the waste transfer throughput and to support maintenance operations. Each system line primarily consists of wet and dry handling areas. The wet handling area includes a cask transport system, cask and DPC preparation system, and a wet assembly handling system. The basket transport system forms the transition between the wet and dry handling areas. The dry handling area includes the dry assembly handling system, assembly drying system, DC preparation system, and DC transport system. Both the wet and dry handling areas are controlled by the control and tracking system. The system operating sequence begins with moving transportation casks to the cask preparation area. The cask preparation operations consist of cask cavity gas sampling, cask venting, cask cool-down, outer lid removal, and inner shield plug lifting fixture attachment. Casks containing bare SNF (no DPC) are filled with water and placed in the cask unloading pool. The inner shield plugs are removed underwater. For casks containing a DPC, the cask lid(s) is removed, and the DPC is penetrated, sampled, vented, and cooled. A DPC lifting fixture is attached and the cask is placed

Outlet temperature measurement correction of Gd fuel assemblies at Dukovany NPP

International Nuclear Information System (INIS)

Jurickova, M.

2008-01-01

In year 2006 we started data processing from the Dukovany NPP operating history database that contained data from the old measurement system VK3 and the new Scorpio-VVER. The work has been done in cooperation with the reactor physicists at Dukovany NPP. Obtained data from database were compared with calculated parameters from 3D diffusion macrocode Mobydick. During the data processing it was found that the Gd fuel assemblies have different time plot of measured assembly outlet temperature compared to the non-Gd fuel assemblies. Experimental studies in RRC KI found that there is insufficient coolant mixing in the region from the fuel bundle to the fuel assembly thermocouple. Due to this fact the thermocouple measure temperature is systematically higher than real temperature. There are two methods to solve this problem. The first method analyses the flow and heat transfer in the region from the fuel bundle to the fuel assembly thermocouple - this method is developed in Skoda JS. The second method statistically studies differences between the measured and calculated temperature by the Mobydick code using the operational history database. Our study is focused on the second method. Several calculation methods for the correction of measured assembly outlet temperature were developed. All correction methods were applied to the measured temperatures from the Dukovany NPP operating history database and the methods were mutually compared. In near future it is planned to compare results of our chosen correction method with modeling method, which is developing in Skoda JS and it is planned to validate both of them. Consequently, the one of these correction methods will be implemented in the modernized Scorpio-VVER for Dukovany NPP. (author)

Storage method for spent fuel assembly

International Nuclear Information System (INIS)

Tajiri, Hiroshi.

1992-01-01

In the present invention, spent fuel assemblies are arranged at a dense pitch in a storage rack by suppressing the reactivity of the assemblies, to increase storage capacity for the spent fuel assemblies. That is, neutron absorbers are filled in the cladding tube of an absorbing rod, and the diameter thereof is substantially equal with that of a fuel rod. A great amount of the absorbing rods are arranged at the outer circumference of the fuel assembly. Then, they are fixed integrally to the fuel assembly and stored in a storage rack. In this case, the storage rack may be constituted only with angle materials which are inexpensive and installed simply. With such a constitution, in the fuel assembly having absorbing rods wound therearound, neutrons are absorbed by absorbing rods and the reactivity is lowered. Accordingly, the assembly arrangement pitch in the storage rack can be made dense. As a result, the storage capacity for the assemblies is increased. (I.S.)

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Vikhorev, Yu.V.; Biryukov, G.I.; Kirilyuk, N.A.; Lobanov, V.N.

1977-01-01

A fuel assembly is proposed for nuclear reactors allowing remote replacement of control rod bundles or their shifting from one assembly to another, i.e., their multipurpose use. This leads to a significant increase in fuel assembly usability. In the fuel assembly the control rod bundle is placed in guide tube channels to which baffles are attached for fuel element spacing. The remote handling of control rods is provided by a hollow cylinder with openings in its lower bottom through which the control rods pass. All control rods in a bundle are mounted to a cross beam which in turn is mounted in the cylinder and is designed for grasping the whole rod bundle by a remotely controlled telescopic mechanism in bundle replacement or shifting. (Z.M.)

Nuclear fuel assembly

International Nuclear Information System (INIS)

Delafosse, Jacques.

1977-01-01

This invention relates to a nuclear fuel assembly for a light or heavy water reactor, or for a fast reactor of the kind with a bundle of cladded pins, maintained parallel to each other in a regular network by an assembly of separate supporting grids, fitted with elastic bearing surfaces on these pins [fr

Self-assembled photosynthesis-inspired light harvesting material and solar cells containing the same

Science.gov (United States)

Lindsey, Jonathan S [Raleigh, NC; Chinnasamy, Muthiah [Raleigh, NC; Fan, Dazhong [Raleigh, NC

2009-12-15

A solar cell is described that comprises: (a) a semiconductor charge separation material; (b) at least one electrode connected to the charge separation material; and (c) a light-harvesting film on the charge separation material, the light-harvesting film comprising non-covalently coupled, self-assembled units of porphyrinic macrocycles. The porphyrinic macrocycles preferably comprise: (i) an intramolecularly coordinated metal; (ii) a first coordinating substituent; and (iii) a second coordinating substituent opposite the first coordinating substituent. The porphyrinic macrocycles can be assembled by repeating intermolecular coordination complexes of the metal, the first coordinating substituent and the second coordinating substituent.

Improving transcriptome assembly through error correction of high-throughput sequence reads

Directory of Open Access Journals (Sweden)

Matthew D. MacManes

2013-07-01

Full Text Available The study of functional genomics, particularly in non-model organisms, has been dramatically improved over the last few years by the use of transcriptomes and RNAseq. While these studies are potentially extremely powerful, a computationally intensive procedure, the de novo construction of a reference transcriptome must be completed as a prerequisite to further analyses. The accurate reference is critically important as all downstream steps, including estimating transcript abundance are critically dependent on the construction of an accurate reference. Though a substantial amount of research has been done on assembly, only recently have the pre-assembly procedures been studied in detail. Specifically, several stand-alone error correction modules have been reported on and, while they have shown to be effective in reducing errors at the level of sequencing reads, how error correction impacts assembly accuracy is largely unknown. Here, we show via use of a simulated and empiric dataset, that applying error correction to sequencing reads has significant positive effects on assembly accuracy, and should be applied to all datasets. A complete collection of commands which will allow for the production of Reptile corrected reads is available at https://github.com/macmanes/error_correction/tree/master/scripts and as File S1.

Vibration analysis of reactor assembly internals for Prototype Fast Breeder Reactor

International Nuclear Information System (INIS)

Chellapandi, P.; Jalaldeen, S.; Srinivasan, R.; Chetal, S.C.; Bhoje, S.B.

2003-01-01

Vibration analysis of the reactor assembly components of 500 MWe Prototype Fast Breeder Reactor (PFBR) is presented. The vibration response of primary pump as well as dynamic forces developed at its supports are predicted numerically. The stiffness properties of hydrostatic bearing are determined by formulating and solving governing fluid and structural mechanics equations. The dynamic forces exerted by pump are used as input data for the dynamic response of reactor assembly components, mainly inner vessel, thermal baffle and control plug. Dynamic response of reactor assembly components is also predicted for the pressure fluctuations caused by sodium free level oscillations. Thermal baffle (weir shell) which is subjected to fluid forces developed at the associated sodium free levels is analysed by formulating and solving a set of non-linear equations for fluids, structures and fluid structure interaction (FSI). The control rod drive mechanism is analysed for response under flow induced forces on the parts subjected to cross flow in the zone just above the core top, taking into account FSI between sheaths of control and safety rod and absorber pin bundle. Based on the analysis results, it is concluded that the reactor assembly internals are free from any risk of mechanical as well as flow induced vibrations. (author)

Investigating organic multilayers by spectroscopic ellipsometry: specific and non-specific interactions of polyhistidine with NTA self-assembled monolayers

Directory of Open Access Journals (Sweden)

Ilaria Solano

2016-04-01

Full Text Available Background: A versatile strategy for protein–surface coupling in biochips exploits the affinity for polyhistidine of the nitrilotriacetic acid (NTA group loaded with Ni(II. Methods based on optical reflectivity measurements such as spectroscopic ellipsometry (SE allow for label-free, non-invasive monitoring of molecule adsorption/desorption at surfaces.Results: This paper describes a SE study about the interaction of hexahistidine (His6 on gold substrates functionalized with a thiolate self-assembled monolayer bearing the NTA end group. By systematically applying the difference spectra method, which emphasizes the small changes of the ellipsometry spectral response upon the nanoscale thickening/thinning of the molecular film, we characterized different steps of the process such as the NTA-functionalization of Au, the adsorption of the His6 layer and its eventual displacement after reaction with competitive ligands. The films were investigated in liquid, and ex situ in ambient air. The SE investigation has been complemented by AFM measurements based on nanolithography methods (nanografting mode.Conclusion: Our approach to the SE data, exploiting the full spectroscopic potential of the method and basic optical models, was able to provide a picture of the variation of the film thickness along the process. The combination of δΔi+1,i(λ, δΨi+1,i(λ (layer-addition mode and δΔ†i',i+1(λ, δΨ†i',i+1(λ (layer-removal mode difference spectra allowed us to clearly disentangle the adsorption of His6 on the Ni-free NTA layer, due to non specific interactions, from the formation of a neatly thicker His6 film induced by the Ni(II-loading of the NTA SAM.

Food Web Assembly Rules for Generalized Lotka-Volterra Equations.

Directory of Open Access Journals (Sweden)

Jan O Haerter

2016-02-01

Full Text Available In food webs, many interacting species coexist despite the restrictions imposed by the competitive exclusion principle and apparent competition. For the generalized Lotka-Volterra equations, sustainable coexistence necessitates nonzero determinant of the interaction matrix. Here we show that this requirement is equivalent to demanding that each species be part of a non-overlapping pairing, which substantially constrains the food web structure. We demonstrate that a stable food web can always be obtained if a non-overlapping pairing exists. If it does not, the matrix rank can be used to quantify the lack of niches, corresponding to unpaired species. For the species richness at each trophic level, we derive the food web assembly rules, which specify sustainable combinations. In neighboring levels, these rules allow the higher level to avert competitive exclusion at the lower, thereby incorporating apparent competition. In agreement with data, the assembly rules predict high species numbers at intermediate levels and thinning at the top and bottom. Using comprehensive food web data, we demonstrate how omnivores or parasites with hosts at multiple trophic levels can loosen the constraints and help obtain coexistence in food webs. Hence, omnivory may be the glue that keeps communities intact even under extinction or ecological release of species.

Food Web Assembly Rules for Generalized Lotka-Volterra Equations.

Science.gov (United States)

Haerter, Jan O; Mitarai, Namiko; Sneppen, Kim

2016-02-01

In food webs, many interacting species coexist despite the restrictions imposed by the competitive exclusion principle and apparent competition. For the generalized Lotka-Volterra equations, sustainable coexistence necessitates nonzero determinant of the interaction matrix. Here we show that this requirement is equivalent to demanding that each species be part of a non-overlapping pairing, which substantially constrains the food web structure. We demonstrate that a stable food web can always be obtained if a non-overlapping pairing exists. If it does not, the matrix rank can be used to quantify the lack of niches, corresponding to unpaired species. For the species richness at each trophic level, we derive the food web assembly rules, which specify sustainable combinations. In neighboring levels, these rules allow the higher level to avert competitive exclusion at the lower, thereby incorporating apparent competition. In agreement with data, the assembly rules predict high species numbers at intermediate levels and thinning at the top and bottom. Using comprehensive food web data, we demonstrate how omnivores or parasites with hosts at multiple trophic levels can loosen the constraints and help obtain coexistence in food webs. Hence, omnivory may be the glue that keeps communities intact even under extinction or ecological release of species.

Design of a high-flux test assembly for the Fusion Materials Irradiation Test Facility

International Nuclear Information System (INIS)

Opperman, E.K.; Vogel, M.A.

1982-01-01

The Fusion Material Test Facility (FMIT) will provide a high flux fusion-like neutron environment in which a variety of structural and non-structural materials irradiations can be conducted. The FMIT experiments, called test assemblies, that are subjected to the highest neutron flux magnitudes and associated heating rates will require forced convection liquid metal cooling systems to remove the neutron deposited power and maintain test specimens at uniform temperatures. A brief description of the FMIT facility and experimental areas is given with emphasis on the design, capabilities and handling of the high flux test assembly

Oral microbial community assembly under the influence of periodontitis.

Science.gov (United States)

Chen, Hongju; Peng, Shuting; Dai, Lin; Zou, Quan; Yi, Bin; Yang, Xianghong; Ma, Zhanshan Sam

2017-01-01

Several ecological hypotheses (e.g., specific plaque, non-specific plaque and keystone pathogen) regarding the etiology of periodontitis have been proposed since the 1990s, most of which have been centered on the concept of dysbiosis associated with periodontitis. Nevertheless, none of the existing hypotheses have presented mechanistic interpretations on how and why dysbiosis actually occurs. Hubbell's neutral theory of biodiversity offers a powerful null model to test hypothesis regarding the mechanism of community assembly and diversity maintenance from the metagenomic sequencing data, which can help to understand the forces that shape the community dynamics such as dysbiosis. Here we reanalyze the dataset from Abusleme et al.'s comparative study of the oral microbial communities from periodontitis patients and healthy individuals. Our study demonstrates that 14 out of 61 communities (23%) passed the neutrality test, a percentage significantly higher than the previous reported neutrality rate of 1% in human microbiome (Li & Ma 2016, Scientific Reports). This suggests that, while the niche selection may play a predominant role in the assembly and diversity maintenance in oral microbiome, the effect of neutral dynamics may not be ignored. However, no statistically significant differences in the neutrality passing rates were detected between the periodontitis and healthy treatments with Fisher's exact probability test and multiple testing corrections, suggesting that the mechanism of community assembly is robust against disturbances such as periodontitis. In addition, our study confirmed previous finding that periodontitis patients exhibited higher biodiversity. These findings suggest that while periodontitis may significantly change the community composition measured by diversity (i.e., the exhibition or 'phenotype' of community assembly), it does not seem to cause the 'mutation' of the 'genotype" (mechanism) of community assembly. We argue that the 'phenotypic

Oral microbial community assembly under the influence of periodontitis.

Directory of Open Access Journals (Sweden)

Hongju Chen

Full Text Available Several ecological hypotheses (e.g., specific plaque, non-specific plaque and keystone pathogen regarding the etiology of periodontitis have been proposed since the 1990s, most of which have been centered on the concept of dysbiosis associated with periodontitis. Nevertheless, none of the existing hypotheses have presented mechanistic interpretations on how and why dysbiosis actually occurs. Hubbell's neutral theory of biodiversity offers a powerful null model to test hypothesis regarding the mechanism of community assembly and diversity maintenance from the metagenomic sequencing data, which can help to understand the forces that shape the community dynamics such as dysbiosis. Here we reanalyze the dataset from Abusleme et al.'s comparative study of the oral microbial communities from periodontitis patients and healthy individuals. Our study demonstrates that 14 out of 61 communities (23% passed the neutrality test, a percentage significantly higher than the previous reported neutrality rate of 1% in human microbiome (Li & Ma 2016, Scientific Reports. This suggests that, while the niche selection may play a predominant role in the assembly and diversity maintenance in oral microbiome, the effect of neutral dynamics may not be ignored. However, no statistically significant differences in the neutrality passing rates were detected between the periodontitis and healthy treatments with Fisher's exact probability test and multiple testing corrections, suggesting that the mechanism of community assembly is robust against disturbances such as periodontitis. In addition, our study confirmed previous finding that periodontitis patients exhibited higher biodiversity. These findings suggest that while periodontitis may significantly change the community composition measured by diversity (i.e., the exhibition or 'phenotype' of community assembly, it does not seem to cause the 'mutation' of the 'genotype" (mechanism of community assembly. We argue that the

Blade attachment assembly

Science.gov (United States)

Garcia-Crespo, Andres Jose; Delvaux, John McConnell; Miller, Diane Patricia

2016-05-03

An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

Magnetic nanoparticle assemblies

CERN Document Server

Trohidou, Kalliopi N

2014-01-01

Magnetic nanoparticles with diameters in the range of a few nanometers are today at the cutting edge of modern technology and innovation because of their use in numerous applications ranging from engineering to biomedicine. A great deal of scientific interest has been focused on the functionalization of magnetic nanoparticle assemblies. The understanding of interparticle interactions is necessary to clarify the physics of these assemblies and their use in the development of high-performance magnetic materials. This book reviews prominent research studies on the static and dynamic magnetic properties of nanoparticle assemblies, gathering together experimental and computational techniques in an effort to reveal their optimized magnetic properties for biomedical use and as ultra-high magnetic recording media.

Nuclear fuel assembly

International Nuclear Information System (INIS)

Hayashi, Hiroshi; Watari, Yoshio; Hizahara, Hiroshi; Masuoka, Ryuzo.

1970-01-01

When exchanging nuclear fuel assemblies during the operation of a nuclear reactor, melting of fuel bodies, and severence of tubular claddings is halted at the time of insertion by furnishing a neutron absorbing material such as B 10 , Cd, Gd or the like at the forward end of the fuel assembly to thereby lower the power peak at the forward ends of the fuel elements to within tolerable levels and thus prevent both fuel liquification and excessive expansion. The neutron absorbing material may be attached in the form of a plate to the fuel assembly forward tie plate, or may be inserted as a pellet into the front end of the tubular cladding. (Owens, K.J.)

Reactor fuel assembly

International Nuclear Information System (INIS)

Anthony, A.J.; Groves, M.D.

1980-01-01

A nuclear reactor fuel assembly having a lower end fitting and actuating means interacting therewith for holding the assembly down on the core support stand against the upward flow of coolant. Locking means for interacting with projections on the support stand are carried by the lower end fitting and are actuated by the movement of an actuating rod operated from above the top of the assembly. In one embodiment of the invention the downward movement of the actuating rod forces a latched spring to move outward into locking engagement with a shoulder on the support stand projections. In another embodiment, the actuating rod is rotated to effect the locking between the end fitting and the projection. (author)

Fuel assembly inspection device

International Nuclear Information System (INIS)

Yaginuma, Yoshitaka

1998-01-01

The present invention provides a device suitable to inspect appearance of fuel assemblies by photographing the appearance of fuel assemblies. Namely, the inspection device of the present invention measures bowing of fuel assembly or each of fuel rods or both of them based on the partially photographed images of fuel assembly. In this case, there is disposed a means which flashily projects images in the form of horizontal line from a direction intersecting obliquely relative to a horizontal cross section of the fuel assembly. A first image processing means separates the projected image pictures including projected images and calculates bowing. A second image processing means replaces the projected image pictures of the projected images based on projected images just before and after the photographing. Then, images for the measurement of bowing and images for inspection can be obtained simultaneously. As a result, the time required for the photographing can be shortened, the time for inspection can be shortened and an effect of preventing deterioration of photographing means by radiation rays can be provided. (I.S.)

Vertical pump assembly

International Nuclear Information System (INIS)

Dohnal, M.; Rosel, J.; Skarka, V.

1988-01-01

The mounting is described of the drive assembly of a vertical pump for nuclear power plants in areas with seismic risk. The assembly is attached to the building floor using flexible and damping elements. The design allows producing seismically resistant pumps without major design changes in the existing types of vertical pumps. (E.S.). 1 fig

Technology for assembling and welding of top and bottom nozzles in fuel assembly

International Nuclear Information System (INIS)

Xia Chenglie; Wan Longfu

1989-10-01

The construction character, technology and sequence of assembling and welding, assembling jig used for preventing from deformation, and acceptance test of welding technology for top and bottom nozzles are presented

Methodologies to determine the Pu content of spent fuel assemblies for input nuclear material accountancy of pyroporcessing

International Nuclear Information System (INIS)

Lee, Taehoon; Shin, Heesung; Kim, Youngsoo; Kim, Hodong; Kwon, Taeje

2011-01-01

This study shows two different non-destructive approaches to determine the Pu mass of spent fuel assemblies, and the analysis results on the errors in their Pu mass. For both methods, the Cm mass of the assembly is obtained based on the neutron measurement results. The Cm ratio of the assembly is determined from the Cm mass and the Pu mass obtained by using either of the two methods. In a comparison of two methods, the second method is simpler than the first and may not need a homogeneously-mixed sample of the spent fuel assembly. On the other hand, the second approach shows larger error in the estimated Pu mass than the first one for many different spent fuel cases of various burnup, initial enrichment, and cooling times. A member state support program for the development of the IAEA safeguards approach for an engineering-scale pyroprocessing facility, which is designated as the Reference Engineering-scale Pyroprocessing Facility(REPF), has been carried out by Korea Atomic Energy Research Institute since 2008. The nuclear material accountancy of the REPF is based on the 'Cm balance' technique. The Pu content of processing materials of pyroprocessing can be determined by measuring the Cm mass of the materials and multiplying it by the Cm ratio. The spent fuel assembly is de-cladded, and the irradiated UO 2 material of the assembly is homogeneously mixed in the homogenization process in order to obtain a representative sample of the spent fuel assembly for determining the mass of Pu, U and Cm elements, as well as the Cm ratio of the campaign. The shipper-receiver difference between the nuclear power plant and HPC of REPF is determined at this point. We found that the error for the Pu mass and Cm ratio determined from the homogenized uranium oxide powder is the most critical for the determination of the material unaccounted for throughout the whole processes. This paper presents two approaches to determine the Pu mass of spent fuel assemblies using non

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

Science.gov (United States)

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

2009-03-01

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

Competitive assembly of South Pacific invasive ant communities

Directory of Open Access Journals (Sweden)

Sarty Megan

2009-01-01

patterns were observed at two spatial scales. Results indicate that abundance-based null models may be more sensitive in detecting non-random patterns in community assembly than species co-occurrences analyses.

Self-assembly and speed distributions of active granular particles

Science.gov (United States)

Sánchez, R.; Díaz-Leyva, P.

2018-06-01

The relationship between the dynamics of self-propelled systems and the self-assembly of structured clusters are studied via the experimental speed distributions of submonolayers of self-propelled granular particles. A distribution developed for non-self-propelled granular particles describes the speed distributions remarkably well, despite some of the assumptions behind its original derivation not being applicable. This is explained in terms of clustering and dissipation being the key phenomena governing this regime.

The Use of Hebbian Cell Assemblies for Nonlinear Computation

DEFF Research Database (Denmark)

Tetzlaff, Christian; Dasgupta, Sakyasingha; Kulvicius, Tomas

2015-01-01

When learning a complex task our nervous system self-organizes large groups of neurons into coherent dynamic activity patterns. During this, a network with multiple, simultaneously active, and computationally powerful cell assemblies is created. How such ordered structures are formed while preser...... computing complex non-linear transforms and - for execution - must cooperate with each other without interference. This mechanism, thus, permits the self-organization of computationally powerful sub-structures in dynamic networks for behavior control....

X-Ray Assembler Data

Data.gov (United States)

U.S. Department of Health & Human Services — Federal regulations require that an assembler who installs one or more certified components of a diagnostic x-ray system submit a report of assembly. This database...

Validation of PWR core seismic models with shaking table tests on interacting scale 1 fuel assemblies

International Nuclear Information System (INIS)

Viallet, E.; Bolsee, G.; Ladouceur, B.; Goubin, T.; Rigaudeau, J.

2003-01-01

The fuel assembly mechanical strength must be justified with respect to the lateral loads under accident conditions, in particular seismic loads. This justification is performed by means of time-history analyses with dynamic models of an assembly row in the core, allowing for assembly deformations, impacts at grid locations and reactor coolant effects. Due to necessary simplifications, the models include 'equivalent' parameters adjusted with respect to dynamic characterisation tests of the fuel assemblies. Complementing such tests on isolated assemblies by an overall model validation with shaking table tests on interacting assemblies is obviously desirable. Seismic tests have been performed by French CEA (Commissariat a l'Energie Atomique) on a row of six full scale fuel assemblies, including two types of 17 x 17 12ft design. The row models are built according to the usual procedure, with preliminary characterisation tests performed on a single assembly. The test-calculation comparisons are made for two test configurations : in air and in water. The relatively large number of accelerograms (15, used for each configuration) is also favourable to significant comparisons. The results are presented for the impact forces at row ends, displacements at mid assembly, and also 'statistical' parameters. Despite a non-negligible scattering in the results obtained with different accelerograms, the calculations prove realistic, and the modelling process is validated with a good confidence level. This satisfactory validation allows to evaluate precisely the margins in the seismic design methodology of the fuel assemblies, and thus to confirm the safety of the plants in case of seismic event. (author)

Beam damage of self-assembled monolayers

International Nuclear Information System (INIS)

Rieke, P.C.; Baer, D.R.; Fryxell, G.E.; Engelhard, M.H.; Porter, M.S.

1993-01-01

X-ray and electron beam damage studies were performed on Br-terminated and methyl-terminated alkylsilane self-assembled monolayers. X-ray beam initiated damage was primarily limited to removal of the labile Br group and did not significantly damage the hydrocarbon chain. Some of the x-ray beam damage could be attributed to low-energy electrons emitted by the non-monochromatic source, but further damage was attributed to secondary electrons produced in the sample by x-ray exposure. Electron beams caused significant damage to the hydrocarbon chains. Maximum damage occurred with a beam energy of 600 eV and a dosage of 6x10 -3 C/cm 2

Nuclear fuel assembly seismic amplitude limiter

International Nuclear Information System (INIS)

Anthony, A.J.

1977-01-01

The ability of a nuclear reactor to withstand high seismic loading is enhanced by including, on each fuel assembly, at least one seismic grid which reduces the magnitude of the possible lateral deflection of the individual fuel elements and the entire fuel assembly. The reduction in possible deflection minimizes the possibility of impact of the spacer grids of one fuel assembly on those of an adjacent fuel assembly and reduces the magnitude of forces associated with any such impact thereby minimizing the possibility of fuel assembly damage as a result of high seismic loading. The seismic grid is mounted from the fuel assembly guide tubes, has greater external dimensions when compared to the fuel assembly spacer grids and normally does not support or otherwise contact the fuel elements. The reduction in possible deflection is achieved through reduction of the clearance between adjacent fuel assemblies made possible by the use in the seismic grid of a high strength material characterized by favorable thermal expansion characteristics and minimal irradiation induced expansion

Chemical reactions directed Peptide self-assembly.

Science.gov (United States)

Rasale, Dnyaneshwar B; Das, Apurba K

2015-05-13

Fabrication of self-assembled nanostructures is one of the important aspects in nanoscience and nanotechnology. The study of self-assembled soft materials remains an area of interest due to their potential applications in biomedicine. The versatile properties of soft materials can be tuned using a bottom up approach of small molecules. Peptide based self-assembly has significant impact in biology because of its unique features such as biocompatibility, straight peptide chain and the presence of different side chain functionality. These unique features explore peptides in various self-assembly process. In this review, we briefly introduce chemical reaction-mediated peptide self-assembly. Herein, we have emphasised enzymes, native chemical ligation and photochemical reactions in the exploration of peptide self-assembly.

Benchmark assemblies of the Los Alamos critical assemblies facility

International Nuclear Information System (INIS)

Dowdy, E.J.

1986-01-01

Several critical assemblies of precisely known materials composition and easily calculated and reproducible geometries have been constructed at the Los Alamos National Laboratory. Some of these machines, notably Jezebel, Flattop, Big Ten, and Godiva, have been used as benchmark assemblies for the comparison of the results of experimental measurements and computation of certain nuclear reaction parameters. These experiments are used to validate both the input nuclear data and the computational methods. The machines and the applications of these machines for integral nuclear data checks are described. (author)

Benchmark assemblies of the Los Alamos Critical Assemblies Facility

International Nuclear Information System (INIS)

Dowdy, E.J.

1985-01-01

Several critical assemblies of precisely known materials composition and easily calculated and reproducible geometries have been constructed at the Los Alamos National Laboratory. Some of these machines, notably Jezebel, Flattop, Big Ten, and Godiva, have been used as benchmark assemblies for the comparison of the results of experimental measurements and computation of certain nuclear reaction parameters. These experiments are used to validate both the input nuclear data and the computational methods. The machines and the applications of these machines for integral nuclear data checks are described

Benchmark assemblies of the Los Alamos critical assemblies facility

International Nuclear Information System (INIS)

Dowdy, E.J.

1985-01-01

Several critical assemblies of precisely known materials composition and easily calculated and reproducible geometries have been constructed at the Los Alamos National Laboratory. Some of these machines, notably Jezebel, Flattop, Big Ten, and Godiva, have been used as benchmark assemblies for the comparison of the results of experimental measurements and computation of certain nuclear reaction parameters. These experiments are used to validate both the input nuclear data and the computational methods. The machines and the applications of these machines for integral nuclear data checks are described

Effective void fraction for a BWR assembly with boiling in the bypass region

International Nuclear Information System (INIS)

Galperin, A.; Segev, M.; Knoglinger, E.

1991-09-01

Average BWR assembly cross-sections for nominal conditions, namely for zero bypass void, can be utilised in the analysis of transient conditions with boiling in the bypass. A model is developed to yield an effective channel void for such conditions. The use of this void in conjunction with the 'nominal conditions' cross section library approximately preserves the assembly K-infinity corresponding to the true channel and bypass voids. The effective void is an augmentation of the actual channel void. The augment is proportional to the bypass-to-channel volume ratio, to the bypass void, and to a weight W which is introduced to quantify the fact that a water molecule in the bypass has a different assembly criticality worth than one in the channel. The formula developed is superior to the practice of choosing W=1, namely a simple, non-weighted, transfer of water from channel to bypass. The use of this approximate effective channel void reproduces actual K-infinity values of assemblies to better than 5 mk, whereas the use of a simple model sometimes misspredicts the assembly K-infinity by 40 mK. The effective void model cannot handle cases in which both channel and bypass void value are high, simply because then the effective void α ch eff becomes meaningless. A method to treat the α eff >1 domain is developed by which corrections to cross sections are provided. Such corrections are synthesised as functions of the assembly parameters. (author) figs., tabs., refs

Molecular self-assembly advances and applications

CERN Document Server

Dequan, Alex Li

2012-01-01

In the past several decades, molecular self-assembly has emerged as one of the main themes in chemistry, biology, and materials science. This book compiles and details cutting-edge research in molecular assemblies ranging from self-organized peptide nanostructures and DNA-chromophore foldamers to supramolecular systems and metal-directed assemblies, even to nanocrystal superparticles and self-assembled microdevices

SP-100 nuclear assembly test: Test assembly functional requirements and system arrangement

International Nuclear Information System (INIS)

Fallas, T.T.; Gluck, R.; Motwani, K.; Clay, H.; O'Neill, G.

1991-01-01

This paper describes the functional requirements and the system that will be tested to validate the reactor, flight shield, and flight controller of the SP-100 Generic Flight System (GFS). The Nuclear Assembly Test (NAT) consists of the test article (SP-100 reactor with control devices and the flight shield) and its supporting systems. The NAT test assembly is being designed by GE. Westinghouse Hanford Company (WHC) is designing the test cell and vacuum vessel system that will contain the NAT test assembly (Renkey et al. 1989). Preliminary design reviews have been completed and the final design is under way

Fuel assembly guide tube

International Nuclear Information System (INIS)

Jabsen, F.S.

1979-01-01

This invention is directed toward a nuclear fuel assembly guide tube arrangement which restrains spacer grid movement due to coolant flow and which offers secondary means for supporting a fuel assembly during handling and transfer operations

Magnetic self-assembly of small parts

Science.gov (United States)

Shetye, Sheetal B.

Modern society's propensity for miniaturized end-user products is compelling electronic manufacturers to assemble and package different micro-scale, multi-technology components in more efficient and cost-effective manners. As the size of the components gets smaller, issues such as part sticking and alignment precision create challenges that slow the throughput of conventional robotic pick-n-place systems. As an alternative, various self-assembly approaches have been proposed to manipulate micro to millimeter scale components in a parallel fashion without human or robotic intervention. In this dissertation, magnetic self-assembly (MSA) is demonstrated as a highly efficient, completely parallel process for assembly of millimeter scale components. MSA is achieved by integrating permanent micromagnets onto component bonding surfaces using wafer-level microfabrication processes. Embedded bonded powder methods are used for fabrication of the magnets. The magnets are then magnetized using pulse magnetization methods, and the wafers are then singulated to form individual components. When the components are randomly mixed together, self-assembly occurs when the intermagnetic forces overcome the mixing forces. Analytical and finite element methods (FEM) are used to study the force interactions between the micromagnets. The multifunctional aspects of MSA are presented through demonstration of part-to-part and part-to-substrate assembly of 1 mm x 1mm x 0.5 mm silicon components. Part-to-part assembly is demonstrated by batch assembly of free-floating parts in a liquid environment with the assembly yield of different magnetic patterns varying from 88% to 90% in 20 s. Part-to-substrate assembly is demonstrated by assembling an ordered array onto a fixed substrate in a dry environment with the assembly yield varying from 86% to 99%. In both cases, diverse magnetic shapes/patterns are used to control the alignment and angular orientation of the components. A mathematical model is

Mechanical Self-Assembly Science and Applications

CERN Document Server

2013-01-01

Mechanical Self-Assembly: Science and Applications introduces a novel category of self-assembly driven by mechanical forces. This book discusses self-assembly in various types of small material structures including thin films, surfaces, and micro- and nano-wires, as well as the practice's potential application in micro and nanoelectronics, MEMS/NEMS, and biomedical engineering. The mechanical self-assembly process is inherently quick, simple, and cost-effective, as well as accessible to a large number of materials, such as curved surfaces for forming three-dimensional small structures. Mechanical self-assembly is complementary to, and sometimes offer advantages over, the traditional micro- and nano-fabrication. This book also: Presents a highly original aspect of the science of self-assembly Describes the novel methods of mechanical assembly used to fabricate a variety of new three-dimensional material structures in simple and cost-effective ways Provides simple insights to a number of biological systems and ...

Directed Self-Assembly of Nanodispersions

Energy Technology Data Exchange (ETDEWEB)

Furst, Eric M [University of Delaware

2013-11-15

Directed self-assembly promises to be the technologically and economically optimal approach to industrial-scale nanotechnology, and will enable the realization of inexpensive, reproducible and active nanostructured materials with tailored photonic, transport and mechanical properties. These new nanomaterials will play a critical role in meeting the 21st century grand challenges of the US, including energy diversity and sustainability, national security and economic competitiveness. The goal of this work was to develop and fundamentally validate methods of directed selfassembly of nanomaterials and nanodispersion processing. The specific aims were: 1. Nanocolloid self-assembly and interactions in AC electric fields. In an effort to reduce the particle sizes used in AC electric field self-assembly to lengthscales, we propose detailed characterizations of field-driven structures and studies of the fundamental underlying particle interactions. We will utilize microscopy and light scattering to assess order-disorder transitions and self-assembled structures under a variety of field and physicochemical conditions. Optical trapping will be used to measure particle interactions. These experiments will be synergetic with calculations of the particle polarizability, enabling us to both validate interactions and predict the order-disorder transition for nanocolloids. 2. Assembly of anisotropic nanocolloids. Particle shape has profound effects on structure and flow behavior of dispersions, and greatly complicates their processing and self-assembly. The methods developed to study the self-assembled structures and underlying particle interactions for dispersions of isotropic nanocolloids will be extended to systems composed of anisotropic particles. This report reviews several key advances that have been made during this project, including, (1) advances in the measurement of particle polarization mechanisms underlying field-directed self-assembly, and (2) progress in the

Inverse Problem in Self-assembly

Science.gov (United States)

Tkachenko, Alexei

2012-02-01

By decorating colloids and nanoparticles with DNA, one can introduce highly selective key-lock interactions between them. This leads to a new class of systems and problems in soft condensed matter physics. In particular, this opens a possibility to solve inverse problem in self-assembly: how to build an arbitrary desired structure with the bottom-up approach? I will present a theoretical and computational analysis of the hierarchical strategy in attacking this problem. It involves self-assembly of particular building blocks (``octopus particles''), that in turn would assemble into the target structure. On a conceptual level, our approach combines elements of three different brands of programmable self assembly: DNA nanotechnology, nanoparticle-DNA assemblies and patchy colloids. I will discuss the general design principles, theoretical and practical limitations of this approach, and illustrate them with our simulation results. Our crucial result is that not only it is possible to design a system that has a given nanostructure as a ground state, but one can also program and optimize the kinetic pathway for its self-assembly.

Active Self-Assembled Spinners: dynamic crystals, transport and induced surface flows

Science.gov (United States)

Snezhko, Alexey; Kokot, Gasper

Strongly interacting colloids driven out-of-equilibrium by an external periodic forcing often develop nontrivial collective dynamics. Active magnetic colloids proved to be excellent model experimental systems to explore emergent behavior and active (out-of-equilibrium) self-assembly phenomena. Ferromagnetic micro-particles, suspended at a liquid interface and energized by a rotational homogeneous alternating magnetic field applied along the supporting interface, spontaneously form ensembles of synchronized self-assembled spinners with well-defined characteristic length. The size and the torque of an individual self-assembled spinner are controlled by the frequency of the driving magnetic field. Experiments reveal a rich collective dynamics in large ensembles of synchronized magnetic spinners that spontaneously form dynamic spinner lattices at the interface in a certain range of the excitation parameters. Non-trivial dynamics inside of the formed spinner lattices is observed. Transport of passive cargo particles and structure of the underlying self-induced surface flows is analyzed. The research was supported by the U.S. DOE, Office of Basic Energy Sciences, Division of Materials Science and Engineering.

Investigation of the structural anisotropy in a self-assembling glycinate layer on Cu(100) by scanning tunneling microscopy and density functional theory calculations

Energy Technology Data Exchange (ETDEWEB)

Kuzmin, Mikhail [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland); Ioffe Physical Technical Institute, Russian Academy of Sciences, 26 Polytekhnicheskaya, St Petersburg 194021 (Russian Federation); Lahtonen, Kimmo; Vuori, Leena [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland); Sánchez-de-Armas, Rocío [Materials Theory Division, Department of Physics and Astronomy, Uppsala University, P.O. Box 516, S75120 Uppsala (Sweden); Hirsimäki, Mika, E-mail: mikahirsi@gmail.com [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland); Valden, Mika [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland)

2017-07-01

Highlights: • Deprotonation reaction of glycine and self-assembly of glycinate is observed on Cu. • Bias-dependent scanning tunneling microscopy indicates two glycinate geometries. • Density functional theory calculations confirm the two non-identical configurations. • Non-identical adsorption explains the anisotropy in adlayer’s electronic structure. - Abstract: Self-assembling organic molecule-metal interfaces exhibiting free-electron like (FEL) states offers an attractive bottom-up approach to fabricating materials for molecular electronics. Accomplishing this, however, requires detailed understanding of the fundamental driving mechanisms behind the self-assembly process. For instance, it is still unresolved as to why the adsorption of glycine ([NH{sub 2}(CH{sub 2})COOH]) on isotropic Cu(100) single crystal surface leads, via deprotonation and self-assembly, to a glycinate ([NH{sub 2}(CH{sub 2})COO–]) layer that exhibits anisotropic FEL behavior. Here, we report on bias-dependent scanning tunneling microscopy (STM) experiments and density functional theory (DFT) calculations for glycine adsorption on Cu(100) single crystal surface. We find that after physical vapor deposition (PVD) of glycine on Cu(100), glycinate self-assembles into an overlayer exhibiting c(2 × 4) and p(2 × 4) symmetries with non-identical adsorption sites. Our findings underscore the intricacy of electrical conductivity in nanomolecular organic overlayers and the critical role the structural anisotropy at molecule-metal interface plays in the fabrication of materials for molecular electronics.

{beta}-Carotene to bacteriochlorophyll c energy transfer in self-assembled aggregates mimicking chlorosomes

Energy Technology Data Exchange (ETDEWEB)

Alster, J. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Praha (Czech Republic); Polivka, T. [Institute of Physical Biology, University of South Bohemia, Zamek 136, 373 33 Nove Hrady (Czech Republic); Biology Centre, Academy of Sciences of the Czech Republic, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic); Arellano, J.B. [Instituto de Recursos Naturales y Agrobiologia de Salamanca (IRNASA-CSIC), Apdo. 257, 37071 Salamanca (Spain); Chabera, P. [Institute of Physical Biology, University of South Bohemia, Zamek 136, 373 33 Nove Hrady (Czech Republic); Vacha, F. [Institute of Physical Biology, University of South Bohemia, Zamek 136, 373 33 Nove Hrady (Czech Republic); Biology Centre, Academy of Sciences of the Czech Republic, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic); Psencik, J., E-mail: psencik@karlov.mff.cuni.cz [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Praha (Czech Republic); Institute of Physical Biology, University of South Bohemia, Zamek 136, 373 33 Nove Hrady (Czech Republic)

2010-07-19

Carotenoids are together with bacteriochlorophylls important constituents of chlorosomes, the light-harvesting antennae of green photosynthetic bacteria. Majority of bacteriochlorophyll molecules form self-assembling aggregates inside the chlorosomes. Aggregates of bacteriochlorophylls with optical properties similar to those of chlorosomes can also be prepared in non-polar organic solvents or in aqueous environments when a suitable non-polar molecule is added. In this work, the ability of {beta}-carotene to induce aggregation of bacteriochlorophyll c in aqueous buffer was studied. Excitation relaxation and energy transfer in the carotenoid-bacteriochlorophyll assemblies were measured using femtosecond and nanosecond transient absorption spectroscopy. A fast, {approx}100-fs energy transfer from the S{sub 2} state of {beta}-carotene to bacteriochlorophyll c was revealed, while no evidence for significant energy transfer from the S{sub 1} state was found. Picosecond formation of the carotenoid triplet state (T{sub 1}) was observed, which was likely generated by singlet homo-fission from the S{sub 1} state of {beta}-carotene.

WHO: World Health Assembly.

Science.gov (United States)

McGregor, A

1992-05-23

1200 delegates from 175 member countries attended the 45th World Health Assembly in Geneva. Everyone at the Assembly ratified measures to prevent and control AIDS. 12 countries intended to do long term planning for community based care for AIDS patients. Further the Assembly denounced instances where countries and individuals denied the gravity of the AIDS pandemic. In fact, it expressed the importance for urgent and intensive action against HIV/AIDS. The assembly backed proposals to prevent and control sexually transmitted diseases that affect AIDS patients, especially hepatitis B. For example, in countries with hepatitis B prevalence 8% (many countries in Sub-Sahara Africa, Asia, the Pacific region, and South America), health officials should introduce hepatitis B vaccine into their existing immunization programs by 1995. By 1997, this vaccine should be part of all immunization programs. The Assembly was aware of the obstacles of establishing reliable cold chains for nationwide distribution, however. Delegates in Committee A objected to the fact that 50% of the populations of developing countries continued to have limited access to essential drugs. They also expressed disapproval in implementation of WHO's 1988 ethical criteria for promotion of drugs which WHO entrusted to the Council for International Organisations of Medical Sciences (CIOMS). CIOMS lacked WHO's status and thus could not effectively monitor drug advertising. In fact, the pharmaceutical industry as well as WHO provided the funds for a meeting of 25 experts to discuss principles included in the ethical criteria. At least 4 countries insisted that WHO have the ultimate authority in monitoring drug advertising. Delegates did adopt a compromise resolution on this topic which required that industry promotion methods be reported to the 1994 Assembly via the Executive Board. The Assembly requested WHO to establish an international advisory committee on nursing and midwifery and to improve the network of

Simulating control rod and fuel assembly motion using moving meshes

Energy Technology Data Exchange (ETDEWEB)

Gilbert, D. [Department of Electrical and Computer Engineering, McMaster University, 1280 Main Street West, Hamilton Ontario, L8S 4K1 (Canada)], E-mail: gilbertdw1@gmail.com; Roman, J.E. [Departamento de Sistemas Informaticos y Computacion, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Garland, Wm. J. [Department of Engineering Physics, McMaster University, 1280 Main Street West, Hamilton Ontario, L8S 4K1 (Canada); Poehlman, W.F.S. [Department of Computing and Software, McMaster University, 1280 Main Street West, Hamilton Ontario, L8S 4K1 (Canada)

2008-02-15

A prerequisite for designing a transient simulation experiment which includes the motion of control and fuel assemblies is the careful verification of a steady state model which computes k{sub eff} versus assembly insertion distance. Previous studies in nuclear engineering have usually approached the problem of the motion of control rods with the use of nonlinear nodal models. Nodal methods employ special approximations for the leading and trailing cells of the moving assemblies to avoid the rod cusping problem which results from the naive volume weighted cell cross-section approximation. A prototype framework called the MOOSE has been developed for modeling moving components in the presence of diffusion phenomena. A linear finite difference model is constructed, solutions for which are computed by SLEPc, a high performance parallel eigenvalue solver. Design techniques for the implementation of a patched non-conformal mesh which links groups of sub-meshes that can move relative to one another are presented. The generation of matrices which represent moving meshes which conserve neutron current at their boundaries, and the performance of the framework when applied to model reactivity insertion experiments is also discussed.

General Assembly

CERN Multimedia

Staff Association

2016-01-01

5th April, 2016 – Ordinary General Assembly of the Staff Association! In the first semester of each year, the Staff Association (SA) invites its members to attend and participate in the Ordinary General Assembly (OGA). This year the OGA will be held on Tuesday, April 5th 2016 from 11:00 to 12:00 in BE Auditorium, Meyrin (6-2-024). During the Ordinary General Assembly, the activity and financial reports of the SA are presented and submitted for approval to the members. This is the occasion to get a global view on the activities of the SA, its financial management, and an opportunity to express one’s opinion, including taking part in the votes. Other points are listed on the agenda, as proposed by the Staff Council. Who can vote? Only “ordinary” members (MPE) of the SA can vote. Associated members (MPA) of the SA and/or affiliated pensioners have a right to vote on those topics that are of direct interest to them. Who can give his/her opinion? The Ordinary General Asse...

Nuclear reactor control assembly

International Nuclear Information System (INIS)

Negron, S.B.

1991-01-01

This patent describes an assembly for providing global power control in a nuclear reactor having the core split into two halves. It comprises a disk assembly formed from at least two disks each machined with an identical surface hole pattern such that rotation of one disk relative to the other causes the hole pattern to open or close, the disk assembly being positioned substantially at the longitudinal center of and coaxial with the core halves; and means for rotating at least one of the disks relative to the other

Apparatus for lifting spent fuel assembly

International Nuclear Information System (INIS)

Hirasawa, Yoshinari; Sato, Isao; Yoneda, Yoshiyuki.

1976-01-01

Object: To increase the efficiency of cooling of a used fuel assembly being moved within a guide tube in the axial direction thereof by directly cooling the assembly with cooling gas fed into the guide tube, thus facilitating the handling of the spent fuel assembly. Structure: An end of a lock portion is inserted into the top portion of a spent fuel assembly, the assembly being hooked on the lock portion. The lock portion is provided on its outer periphery with a seal member and a centering member and at its tip with a pawl capable of being projected and retracted in the radial direction. Thus, when the lock portion is moved along the guide tube, the used fuel assembly can be moved along the guide tube by maintaining the concentric relation thereto. Meanwhile, when cooling gas is fed into the guide tube, it is blown into the used fuel assembly to directly cool the same. Thus, the cooling efficiency can be increased. (Moriyama, M.)

Production and cross-sectional characterization of aligned co-electrospun hollow microfibrous bulk assemblies

Energy Technology Data Exchange (ETDEWEB)

Zhou, Feng-Lei [Centre for Imaging Sciences, The University of Manchester, Manchester M13 9PT (United Kingdom); The School of Materials, The University of Manchester, Manchester M13 9PL (United Kingdom); CRUK-EPSRC Cancer Imaging Centre in Cambridge and Manchester (United Kingdom); Parker, Geoff J.M., E-mail: geoff.parker@manchester.ac.uk [Centre for Imaging Sciences, The University of Manchester, Manchester M13 9PT (United Kingdom); CRUK-EPSRC Cancer Imaging Centre in Cambridge and Manchester (United Kingdom); Eichhorn, Stephen J. [College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom); Hubbard Cristinacce, Penny L. [Centre for Imaging Sciences, The University of Manchester, Manchester M13 9PT (United Kingdom); School of Psychological Sciences, University of Manchester, Manchester M13 9PT (United Kingdom)

2015-11-15

The development of co-electrospun (co-ES) hollow microfibrous assemblies of an appreciable thickness is critical for many practical applications, including filtration membranes and tissue-mimicking scaffolds. In this study, thick uniaxially aligned hollow microfibrous assemblies forming fiber bundles and strips were prepared by co-ES of polycaprolactone (PCL) and polyethylene oxide (PEO) as shell and core materials, respectively. Hollow microfiber bundles were deposited on a fixed rotating disc, which resulted in non-controllable cross-sectional shapes on a macroscopic scale. In comparison, fiber strips were produced with tuneable thickness and width by additionally employing an x–y translation stage in co-ES. Scanning electron microscopy (SEM) images of cross-sections of fiber assemblies were analyzed to investigate the effects of production time (from 0.5 h to 12 h), core flow rate (from 0.8 mL/h to 2.0 mL/h) and/or translation speed (from 0.2 mm/s to 5 mm/s) on the pores and porosity. We observed significant changes in pore size and shape with core flow rate but the influence of production time varied; five strips produced under the same conditions had reasonably good size and porosity reproducibility; pore sizes didn't vary significantly from strip bottom to surface, although the porosity gradually decreased and then returned to the initial level. - Highlights: • Hollow microfibrous assemblies based on co-electrospinning are demonstrated. • The thickness and width of co-electrospun strips were controllable. • Cross-sections of fibres had non-normally distributed pore sizes and shapes. • Cross-sections were significantly influenced by production time and flow rate. • Co-electrospun strips had reasonably good reproducible cross-sections.

De novo assembly, characterization and functional annotation of pineapple fruit transcriptome through massively parallel sequencing.

Science.gov (United States)

Ong, Wen Dee; Voo, Lok-Yung Christopher; Kumar, Vijay Subbiah

2012-01-01

Pineapple (Ananas comosus var. comosus), is an important tropical non-climacteric fruit with high commercial potential. Understanding the mechanism and processes underlying fruit ripening would enable scientists to enhance the improvement of quality traits such as, flavor, texture, appearance and fruit sweetness. Although, the pineapple is an important fruit, there is insufficient transcriptomic or genomic information that is available in public databases. Application of high throughput transcriptome sequencing to profile the pineapple fruit transcripts is therefore needed. To facilitate this, we have performed transcriptome sequencing of ripe yellow pineapple fruit flesh using Illumina technology. About 4.7 millions Illumina paired-end reads were generated and assembled using the Velvet de novo assembler. The assembly produced 28,728 unique transcripts with a mean length of approximately 200 bp. Sequence similarity search against non-redundant NCBI database identified a total of 16,932 unique transcripts (58.93%) with significant hits. Out of these, 15,507 unique transcripts were assigned to gene ontology terms. Functional annotation against Kyoto Encyclopedia of Genes and Genomes pathway database identified 13,598 unique transcripts (47.33%) which were mapped to 126 pathways. The assembly revealed many transcripts that were previously unknown. The unique transcripts derived from this work have rapidly increased of the number of the pineapple fruit mRNA transcripts as it is now available in public databases. This information can be further utilized in gene expression, genomics and other functional genomics studies in pineapple.

Cooperative effects of fibronectin matrix assembly and initial cell-substrate adhesion strength in cellular self-assembly.

Science.gov (United States)

Brennan, James R; Hocking, Denise C

2016-03-01

The cell-dependent polymerization of intercellular fibronectin fibrils can stimulate cells to self-assemble into multicellular structures. The local physical cues that support fibronectin-mediated cellular self-assembly are largely unknown. Here, fibronectin matrix analogs were used as synthetic adhesive substrates to model cell-matrix fibronectin fibrils having different integrin-binding specificity, affinity, and/or density. We utilized this model to quantitatively assess the relationship between adhesive forces derived from cell-substrate interactions and the ability of fibronectin fibril assembly to induce cellular self-assembly. Results indicate that the strength of initial, rather than mature, cell-substrate attachments correlates with the ability of substrates to support fibronectin-mediated cellular self-assembly. The cellular response to soluble fibronectin was bimodal and independent of the integrin-binding specificity of the substrate; increasing soluble fibronectin levels above a critical threshold increased aggregate cohesion on permissive substrates. Once aggregates formed, continuous fibronectin polymerization was necessary to maintain cohesion. During self-assembly, soluble fibronectin decreased cell-substrate adhesion strength and induced aggregate cohesion via a Rho-dependent mechanism, suggesting that the balance of contractile forces derived from fibronectin fibrils within cell-cell versus cell-substrate adhesions controls self-assembly and aggregate cohesion. Thus, initial cell-substrate attachment strength may provide a quantitative basis with which to build predictive models of fibronectin-mediated microtissue fabrication on a variety of substrates. Cellular self-assembly is a process by which cells and extracellular matrix (ECM) proteins spontaneously organize into three-dimensional (3D) tissues in the absence of external forces. Cellular self-assembly can be initiated in vitro, and represents a potential tool for tissue engineers to

Biologic Constraints on Modelling Virus Assembly

Directory of Open Access Journals (Sweden)

Robert L. Garcea

2008-01-01

Full Text Available The mathematic modelling of icosahedral virus assembly has drawn increasing interest because of the symmetric geometry of the outer shell structures. Many models involve equilibrium expressions of subunit binding, with reversible subunit additions forming various intermediate structures. The underlying assumption is that a final lowest energy state drives the equilibrium toward assembly. In their simplest forms, these models have explained why high subunit protein concentrations and strong subunit association constants can result in kinetic traps forming off pathway partial and aberrant structures. However, the cell biology of virus assembly is exceedingly complex. The biochemistry and biology of polyoma and papillomavirus assembly described here illustrates many of these specific issues. Variables include the use of cellular ‘chaperone’ proteins as mediators of assembly fidelity, the coupling of assembly to encapsidation of a specific nucleic acid genome, the use of cellular structures as ‘workbenches’ upon which assembly occurs, and the underlying problem of making a capsid structure that is metastable and capable of rapid disassembly upon infection. Although formidable to model, incorporating these considerations could advance the relevance of mathematical models of virus assembly to the real world.

Alignment of 1000 Genomes Project reads to reference assembly GRCh38.

Science.gov (United States)

Zheng-Bradley, Xiangqun; Streeter, Ian; Fairley, Susan; Richardson, David; Clarke, Laura; Flicek, Paul

2017-07-01

The 1000 Genomes Project produced more than 100 trillion basepairs of short read sequence from more than 2600 samples in 26 populations over a period of five years. In its final phase, the project released over 85 million genotyped and phased variants on human reference genome assembly GRCh37. An updated reference assembly, GRCh38, was released in late 2013, but there was insufficient time for the final phase of the project analysis to change to the new assembly. Although it is possible to lift the coordinates of the 1000 Genomes Project variants to the new assembly, this is a potentially error-prone process as coordinate remapping is most appropriate only for non-repetitive regions of the genome and those that did not see significant change between the two assemblies. It will also miss variants in any region that was newly added to GRCh38. Thus, to produce the highest quality variants and genotypes on GRCh38, the best strategy is to realign the reads and recall the variants based on the new alignment. As the first step of variant calling for the 1000 Genomes Project data, we have finished remapping all of the 1000 Genomes sequence reads to GRCh38 with alternative scaffold-aware BWA-MEM. The resulting alignments are available as CRAM, a reference-based sequence compression format. The data have been released on our FTP site and are also available from European Nucleotide Archive to facilitate researchers discovering variants on the primary sequences and alternative contigs of GRCh38. © The Authors 2017. Published by Oxford University Press.

Consequences of mis-loading and the power distribution in bowed fuel assemblies

International Nuclear Information System (INIS)

Andersson, Magnus

2002-04-01

The thesis is divided in two parts. The first part will investigate consequences of a mis-loaded fuel assembly in Ringhals 3, which is a pressurised water reactor (PWR). The aim of this work is to show that there are no or very small benefits from making an additional flux map at 30 % power in order to detect anomalies. Out of the 17 simulations, there exists only one type of mis-loading, which leads to problems. The case, which leads to problems, is when a Gd fitted assembly changes place with a non Gd. This leads to a too high power peaking factor and increased quadrant power tilt. The gain of a flux map at 30% power is small

Consequences of mis-loading and the power distribution in bowed fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Andersson, Magnus

2002-04-01

The thesis is divided in two parts. The first part will investigate consequences of a mis-loaded fuel assembly in Ringhals 3, which is a pressurised water reactor (PWR). The aim of this work is to show that there are no or very small benefits from making an additional flux map at 30 % power in order to detect anomalies. Out of the 17 simulations, there exists only one type of mis-loading, which leads to problems. The case, which leads to problems, is when a Gd fitted assembly changes place with a non Gd. This leads to a too high power peaking factor and increased quadrant power tilt. The gain of a flux map at 30% power is small.

Self-Assembly of Ureido-Pyrimidinone Dimers into One-Dimensional Stacks by Lateral Hydrogen Bonding

NARCIS (Netherlands)

Nieuwenhuizen, Marko M.L.; de Greef, Tom F.A.; van der Bruggen, Rob L.J.; Paulusse, Jos Marie Johannes; Appel, Wilco P.J.; Smulders, Maarten M.J.; Sijbesma, Rint P.; Meijer, E.W.

2010-01-01

Ureido-pyrimidinone (UPy) dimers substituted with an additional urea functionality self-assemble into one-dimensional stacks in various solvents through lateral non-covalent interactions. 1H NMR and DOSY studies in CDCl3 suggest the formation of short stacks (<10), whereas temperature-dependent

Self-assembled nanomaterials for photoacoustic imaging

Science.gov (United States)

Wang, Lei; Yang, Pei-Pei; Zhao, Xiao-Xiao; Wang, Hao

2016-01-01

In recent years, extensive endeavors have been paid to construct functional self-assembled nanomaterials for various applications such as catalysis, separation, energy and biomedicines. To date, different strategies have been developed for preparing nanomaterials with diversified structures and functionalities via fine tuning of self-assembled building blocks. In terms of biomedical applications, bioimaging technologies are urgently calling for high-efficient probes/contrast agents for high-performance bioimaging. Photoacoustic (PA) imaging is an emerging whole-body imaging modality offering high spatial resolution, deep penetration and high contrast in vivo. The self-assembled nanomaterials show high stability in vivo, specific tolerance to sterilization and prolonged half-life stability and desirable targeting properties, which is a kind of promising PA contrast agents for biomedical imaging. Herein, we focus on summarizing recent advances in smart self-assembled nanomaterials with NIR absorption as PA contrast agents for biomedical imaging. According to the preparation strategy of the contrast agents, the self-assembled nanomaterials are categorized into two groups, i.e., the ex situ and in situ self-assembled nanomaterials. The driving forces, assembly modes and regulation of PA properties of self-assembled nanomaterials and their applications for long-term imaging, enzyme activity detection and aggregation-induced retention (AIR) effect for diagnosis and therapy are emphasized. Finally, we conclude with an outlook towards future developments of self-assembled nanomaterials for PA imaging.

Self-assembled nanomaterials for photoacoustic imaging.

Science.gov (United States)

Wang, Lei; Yang, Pei-Pei; Zhao, Xiao-Xiao; Wang, Hao

2016-02-07

In recent years, extensive endeavors have been paid to construct functional self-assembled nanomaterials for various applications such as catalysis, separation, energy and biomedicines. To date, different strategies have been developed for preparing nanomaterials with diversified structures and functionalities via fine tuning of self-assembled building blocks. In terms of biomedical applications, bioimaging technologies are urgently calling for high-efficient probes/contrast agents for high-performance bioimaging. Photoacoustic (PA) imaging is an emerging whole-body imaging modality offering high spatial resolution, deep penetration and high contrast in vivo. The self-assembled nanomaterials show high stability in vivo, specific tolerance to sterilization and prolonged half-life stability and desirable targeting properties, which is a kind of promising PA contrast agents for biomedical imaging. Herein, we focus on summarizing recent advances in smart self-assembled nanomaterials with NIR absorption as PA contrast agents for biomedical imaging. According to the preparation strategy of the contrast agents, the self-assembled nanomaterials are categorized into two groups, i.e., the ex situ and in situ self-assembled nanomaterials. The driving forces, assembly modes and regulation of PA properties of self-assembled nanomaterials and their applications for long-term imaging, enzyme activity detection and aggregation-induced retention (AIR) effect for diagnosis and therapy are emphasized. Finally, we conclude with an outlook towards future developments of self-assembled nanomaterials for PA imaging.

Fuel cell sub-assembly

Science.gov (United States)

Chi, Chang V.

1983-01-01

A fuel cell sub-assembly comprising a plurality of fuel cells, a first section of a cooling means disposed at an end of the assembly and means for connecting the fuel cells and first section together to form a unitary structure.

Growth of rat dorsal root ganglion neurons on a novel self-assembling scaffold containing IKVAV sequence

Energy Technology Data Exchange (ETDEWEB)

Zou Zhenwei; Zheng Qixin [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China); Wu Yongchao, E-mail: wuyongchao@hotmail.com [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China); Song Yulin; Wu Bin [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China)

2009-08-31

The potential benefits of self-assembly in synthesizing materials for the treatment of both peripheral and central nervous system disorders are tremendous. In this study, we synthesized peptide-amphiphile (PA) molecules containing IKVAV sequence and induced self-assembly of the PA solutions in vitro to form nanofiber gels. Then, we tested the characterization of gels by transmission electron microscopy and demonstrated the biocompatibility of this gel towards rat dorsal root ganglion neurons. The nanofiber gel was formed by self-assembly of IKVAV PA molecules, which was triggered by metal ions. The fibers were 7-8 nm in diameter and with lengths of hundreds of nanometers. Gels were shown to be non-toxic to neurons and able to promote neurons adhesion and neurite sprouting. The results indicated that the self-assembling scaffold containing IKVAV sequence had excellent biocompatibility with adult sensory neurons and could be useful in nerve tissue engineering.

Fabrication of Nanostructures Using Self-Assembled Peptides as Templates

DEFF Research Database (Denmark)

Castillo, Jaime

2015-01-01

the advantages of diphenylalanine are explained step by step offering new alternatives to fabricate nanostructures in a simple and rapid way. The chapter is complemented with techniques to manipulate the self-assembled diphenylalanine nanostructures without changing its properties during the manipulation process.......This chapter evaluates the use of a short-aromatic dipeptide, diphenylalanine, as a template in the fabrication of new nanostructures (nanowires, coaxial nanocables, nanochannels) using materials such as silicon, conducting and non-conducting polymers. Diphenylalanine self...

Rapid electrostatics-assisted layer-by-layer assembly of near-infrared-active colloidal photonic crystals.

Science.gov (United States)

Askar, Khalid; Leo, Sin-Yen; Xu, Can; Liu, Danielle; Jiang, Peng

2016-11-15

Here we report a rapid and scalable bottom-up technique for layer-by-layer (LBL) assembling near-infrared-active colloidal photonic crystals consisting of large (⩾1μm) silica microspheres. By combining a new electrostatics-assisted colloidal transferring approach with spontaneous colloidal crystallization at an air/water interface, we have demonstrated that the crystal transfer speed of traditional Langmuir-Blodgett-based colloidal assembly technologies can be enhanced by nearly 2 orders of magnitude. Importantly, the crystalline quality of the resultant photonic crystals is not compromised by this rapid colloidal assembly approach. They exhibit thickness-dependent near-infrared stop bands and well-defined Fabry-Perot fringes in the specular transmission and reflection spectra, which match well with the theoretical calculations using a scalar-wave approximation model and Fabry-Perot analysis. This simple yet scalable bottom-up technology can significantly improve the throughput in assembling large-area, multilayer colloidal crystals, which are of great technological importance in a variety of optical and non-optical applications ranging from all-optical integrated circuits to tissue engineering. Copyright © 2016 Elsevier Inc. All rights reserved.

Data report for the NRC/PNL Halden Assembly IFA-432

International Nuclear Information System (INIS)

Hann, C.R.; Bradley, E.R.; Cunningham, M.E.; Lanning, D.D.; Marshall, R.K.; Williford, R.E.

1978-08-01

The report presents the in-reactor data collected from the NRC/PNL Halden Assembly IFA-432 as a part of the program entitled ''Experimental Vertification of Steady State Fuel Codes,'' sponsored by the Fuel Behavior Research Branch of the USNRC. The purpose of this program is to reduce the uncertainties of calculating the thermal stored energy in an operating nuclear fuel rod. The report presents fuel centerline thermocouple readings, cladding elongation monitor readings, rod internal pressure readings, and neutron detector readings. The neutron detector readings were corrected to represent rod local powers at the thermocouple locations. These data are presented in the form of plots of the variables versus time during the portion of the irradiation period from December 1975 to January 1978. Also included are descriptions of the test rationale, assembly and rod designs, test facility, instrument array and calibration, and data processing methods. Topical reports discussing specific aspects and results of the data analysis are referenced. As of May 1978, the assembly burnup had reached its design goal of 20,000 MWd/MTM. However, it has been decided to leave the assembly in core to collect high burnup fission gas release data. The xenon-filled Rod 4 was replaced with the non-instrumented Rod 8 (Rod 1 design) after the first cycle. Six of the twelve original thermocouples, four of the six cladding elongation monitors, all SPND'S and all pressure transducers remain operable at this writing

Non-destructive failure analysis and measurement for molded devices and complex assemblies with X-ray CT and 3D image processing techniques

International Nuclear Information System (INIS)

Yin, Xiaoming; Liew, Seaw Jia; Jiang, Ting Ying; Xu, Jian; Kakarala, Ramakrishna

2013-01-01

In both automotive and healthcare sectors, reliable failure analysis and accurate measurement of molded devices and complex assemblies are important. Current methods of failure analysis and measurement require these molded parts to be cross-sectioned so that internal features or dimensions can be accessible. As a result, the parts are deemed unusable and additional failure introduced by sectioning may cause misinterpretation of the results. X-ray CT and 3D image processing techniques provide a new nondestructive solution for failure analysis and measurement of molded devices and complex assemblies. These techniques simplify failure analysis and measurement of molded devices and assemblies, and improve the productivity of molding manufacturing significantly.

Stochastic modeling of virus capsid assembly pathways

Science.gov (United States)

Schwartz, Russell

2009-03-01

Virus capsids have become a key model system for understanding self-assembly due to their high complexity, robust and efficient assembly processes, and experimental tractability. Our ability to directly examine and manipulate capsid assembly kinetics in detail nonetheless remains limited, creating a need for computer models that can infer experimentally inaccessible features of the assembly process and explore the effects of hypothetical manipulations on assembly trajectories. We have developed novel algorithms for stochastic simulation of capsid assembly [1,2] that allow us to model capsid assembly over broad parameter spaces [3]. We apply these methods to study the nature of assembly pathway control in virus capsids as well as their sensitivity to assembly conditions and possible experimental interventions. [4pt] [1] F. Jamalyaria, R. Rohlfs, and R. Schwartz. J Comp Phys 204, 100 (2005). [0pt] [2] N. Misra and R. Schwartz. J Chem Phys 129, in press (2008). [0pt] [3] B. Sweeney, T. Zhang, and R. Schwartz. Biophys J 94, 772 (2008).

Faucet: streaming de novo assembly graph construction.

Science.gov (United States)

Rozov, Roye; Goldshlager, Gil; Halperin, Eran; Shamir, Ron

2018-01-01

We present Faucet, a two-pass streaming algorithm for assembly graph construction. Faucet builds an assembly graph incrementally as each read is processed. Thus, reads need not be stored locally, as they can be processed while downloading data and then discarded. We demonstrate this functionality by performing streaming graph assembly of publicly available data, and observe that the ratio of disk use to raw data size decreases as coverage is increased. Faucet pairs the de Bruijn graph obtained from the reads with additional meta-data derived from them. We show these metadata-coverage counts collected at junction k-mers and connections bridging between junction pairs-contain most salient information needed for assembly, and demonstrate they enable cleaning of metagenome assembly graphs, greatly improving contiguity while maintaining accuracy. We compared Fauceted resource use and assembly quality to state of the art metagenome assemblers, as well as leading resource-efficient genome assemblers. Faucet used orders of magnitude less time and disk space than the specialized metagenome assemblers MetaSPAdes and Megahit, while also improving on their memory use; this broadly matched performance of other assemblers optimizing resource efficiency-namely, Minia and LightAssembler. However, on metagenomes tested, Faucet,o outputs had 14-110% higher mean NGA50 lengths compared with Minia, and 2- to 11-fold higher mean NGA50 lengths compared with LightAssembler, the only other streaming assembler available. Faucet is available at https://github.com/Shamir-Lab/Faucet. rshamir@tau.ac.il or eranhalperin@gmail.com. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

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

Self-assembly scenarios of patchy colloidal particles in two dimensions

International Nuclear Information System (INIS)

Doppelbauer, Guenther; Bianchi, Emanuela; Kahl, Gerhard

2010-01-01

We have investigated the self-assembly scenario of patchy colloidal particles in a two-dimensional system. The energetically most favourable ordered particle arrangements have been identified via an optimization tool that is based on genetic algorithms. Assuming different simple models for patchy colloidal particles, which include binary mixtures as well as attraction and repulsion between the patches, we could identify a broad variety of highly non-trivial ordered structures. The strategies of the systems to self-assemble become evident from a systematic variation of the pressure: (i) saturation of patch bonds at low pressure and close packing at high pressure and (ii) for intermediate pressure values, the strategy is governed by a trade-off between these two energetic aspects. The present study is yet another demonstration of the efficiency and the high reliability of genetic algorithms as versatile optimization tools.

A protein interaction map of the kalimantacin biosynthesis assembly line

Directory of Open Access Journals (Sweden)

Birgit Uytterhoeven

2016-11-01

Full Text Available The antimicrobial secondary metabolite kalimantacin is produced by a hybrid polyketide/ non-ribosomal peptide system in Pseudomonas fluorescens BCCM_ID9359. In this study, the kalimantacin biosynthesis gene cluster is analyzed by yeast two-hybrid analysis, creating a protein-protein interaction map of the entire assembly line. In total, 28 potential interactions were identified, of which 13 could be confirmed further. These interactions include the dimerization of ketosynthase domains, a link between assembly line modules 9 and 10, and a specific interaction between the trans-acting enoyl reductase BatK and the carrier proteins of modules 8 and 10. These interactions reveal fundamental insight into the biosynthesis of secondary metabolites.This study is the first to reveal interactions in a complete biosynthetic pathway. Similar future studies could build a strong basis for engineering strategies in such clusters.

Liquid-liquid interfacial nanoparticle assemblies

Science.gov (United States)

Emrick, Todd S [South Deerfield, MA; Russell, Thomas P [Amherst, MA; Dinsmore, Anthony [Amherst, MA; Skaff, Habib [Amherst, MA; Lin, Yao [Amherst, MA

2008-12-30

Self-assembly of nanoparticles at the interface between two fluids, and methods to control such self-assembly process, e.g., the surface density of particles assembling at the interface; to utilize the assembled nanoparticles and their ligands in fabrication of capsules, where the elastic properties of the capsules can be varied from soft to tough; to develop capsules with well-defined porosities for ultimate use as delivery systems; and to develop chemistries whereby multiple ligands or ligands with multiple functionalities can be attached to the nanoparticles to promote the interfacial segregation and assembly of the nanoparticles. Certain embodiments use cadmium selenide (CdSe) nanoparticles, since the photoluminescence of the particles provides a convenient means by which the spatial location and organization of the particles can be probed. However, the systems and methodologies presented here are general and can, with suitable modification of the chemistries, be adapted to any type of nanoparticle.

Burnup verification measurements on spent fuel assemblies at Arkansas Nuclear One

International Nuclear Information System (INIS)

Ewing, R.I.

1995-01-01

Burnup verification measurements have been performed using the Fork system at Arkansas Nuclear One, Units 1 and 2, operated by Energy Operations, Inc. Passive neutron and gamma-ray measurements on individual spent fuel assemblies were correlated with the reactor records for burnup, cooling time, and initial enrichment. The correlation generates an internal calibration for the system in the form of a power law determined by a least squares fit to the neutron data. The values of the exponent in the power laws were 3.83 and 4.35 for Units 1 and 2, respectively. The average deviation of the reactor burnup records from the calibration determined from the measurements is a measure of the random error in the burnup records. The observed average deviations were 2.7% and 3.5% for assemblies at Units 1 and 2, respectively, indicating a high degree of consistency in the reactor records. Two non-standard assemblies containing neutron sources were studied at Unit 2. No anomalous measurements were observed among the standard assemblies at either Unit. The effectiveness of the Fork system for verification of reactor records is due to the sensitivity of the neutron yield to burnup, the self-calibration generated by a series of measurements, the redundancy provided by three independent detection systems, and the operational simplicity and flexibility of the design

SolidWorks 2011 Assemblies Bible

CERN Document Server

Lombard, Matt

2011-01-01

A fan of the SolidWorks Bible, but want more detail on assemblies? Here you go. SolidWorks fans have long sought more detail on SolidWorks topics, and now you have it. We took our popular SolidWorks Bible, divided it into two books (SolidWorks 2011 Assemblies Bible and SolidWorks 2011 Parts Bible) and packed each new book with a host of items from your wish lists, such as more extensive coverage of the basics, additional tutorials, and expanded coverage of topics largely ignored by other books. This SolidWorks 2011 Assemblies Bible shows you how to organize parts data to create assemblies or s

Airfoil nozzle and shroud assembly

Science.gov (United States)

Shaffer, J.E.; Norton, P.F.

1997-06-03

An airfoil and nozzle assembly are disclosed including an outer shroud having a plurality of vane members attached to an inner surface and having a cantilevered end. The assembly further includes a inner shroud being formed by a plurality of segments. Each of the segments having a first end and a second end and having a recess positioned in each of the ends. The cantilevered end of the vane member being positioned in the recess. The airfoil and nozzle assembly being made from a material having a lower rate of thermal expansion than that of the components to which the airfoil and nozzle assembly is attached. 5 figs.

Scaffold-free, label-free and nozzle-free biofabrication technology using magnetic levitational assembly.

Science.gov (United States)

Parfenov, Vladislav A; Koudan, Elizaveta V; Bulanova, Elena A; Karalkin, Pavel A; Pereira, Frederico DAS; Norkin, Nikita E; Knyazeva, Alisa D; Gryadunova, Anna A; Petrov, Oleg F; Vasiliev, M M; Myasnikov, Maxim; Chernikov, Valery P; Kasyanov, Vladimir A; Marchenkov, Artem Yu; Brakke, Kenneth A; Khesuani, Yusef D; Demirci, Utkan; Mironov, Vladimir A

2018-05-31

Tissue spheroids have been proposed as building blocks in 3D biofabrication. Conventional magnetic force-driven 2D patterning of tissue spheroids requires prior cell labeling by magnetic nanoparticles, meanwhile a label-free approach for 3D magnetic levitational assembly has been introduced. Here we present first-time report on rapid assembly of 3D tissue construct using scaffold-free, nozzle-free and label-free magnetic levitation of tissue spheroids. Chondrospheres of standard size, shape and capable to fusion have been biofabricated from primary sheep chondrocytes using non-adhesive technology. Label-free magnetic levitation was performed using a prototype device equipped with permanent magnets in presence of gadolinium (Gd3+) in culture media, which enables magnetic levitation. Mathematical modeling and computer simulations were used for prediction of magnetic field and kinetics of tissue spheroids assembly into 3D tissue constructs. First, we used polystyrene beads to simulate the assembly of tissue spheroids and to determine the optimal settings for magnetic levitation in presence of Gd3+. Second, we proved the ability of chondrospheres to assemble rapidly into 3D tissue construct in the permanent magnetic field in the presence of Gd3+. Thus, scaffold- and label-free magnetic levitation of tissue spheroids is a promising approach for rapid 3D biofabrication and attractive alternative to label-based magnetic force-driven tissue engineering. . © 2018 IOP Publishing Ltd.

Capacitor assembly and related method of forming

Science.gov (United States)

Zhang, Lili; Tan, Daniel Qi; Sullivan, Jeffrey S.

2017-12-19

A capacitor assembly is disclosed. The capacitor assembly includes a housing. The capacitor assembly further includes a plurality of capacitors disposed within the housing. Furthermore, the capacitor assembly includes a thermally conductive article disposed about at least a portion of a capacitor body of the capacitors, and in thermal contact with the capacitor body. Moreover, the capacitor assembly also includes a heat sink disposed within the housing and in thermal contact with at least a portion of the housing and the thermally conductive article such that the heat sink is configured to remove heat from the capacitor in a radial direction of the capacitor assembly. Further, a method of forming the capacitor assembly is also presented.

Gas separation membrane module assembly

Science.gov (United States)

Wynn, Nicholas P [Palo Alto, CA; Fulton, Donald A [Fairfield, CA

2009-03-31

A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membranes, arranged within a housing. The housing contains a tube sheet that divides the space within the housing into two gas-tight spaces. A permeate collection system within the housing gathers permeate gas from the tubes for discharge from the housing.

3D Programmable Micro Self Assembly

National Research Council Canada - National Science Library

Bohringer, Karl F; Parviz, Babak A; Klavins, Eric

2005-01-01

.... We have developed a "self assembly tool box" consisting of a range of methods for micro-scale self-assembly in 2D and 3D We have shown physical demonstrations of simple 3D self-assemblies which lead...

Non-proliferation and international safeguards. [Booklet by IAEA

Energy Technology Data Exchange (ETDEWEB)

1978-01-01

This booklet consists of 13 separate, brief analyses related to the subject title, namely: The International Scope of IAEA Safeguards; Application of Safeguards Procedures; Computer-Based Safeguards Information and Accounting System; IAEA Training Activities Related to State Systems of Nuclear Materials Accountancy and Control; Surveillance and Containment Measures to Support IAEA Safeguards; International Plutonium Management; Safeguards for Reprocessing and Enrichment Plants; Non-Destructive Assay: Instruments and Techniques for Agency Safeguards; The Safeguards Analytical Laboratory: Its Functions and Analytical Facilities; Resolution of the UN General Assembly on the Treaty on the Non-Proliferation of Nuclear Weapons of 12 June 1968; The Treaty on the Non-Proliferation of Nuclear Weapons; Final Declaration of the Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons, May 1975; Resolutions on the IAEA's Work in the Field of the Peaceful Uses of Atomic Energy, adopted by the UN General Assembly on 8 and 12 December, 1977; and a Map on the NPT situation in the world (with explanations).

A comparative evaluation of genome assembly reconciliation tools.

Science.gov (United States)

Alhakami, Hind; Mirebrahim, Hamid; Lonardi, Stefano

2017-05-18

The majority of eukaryotic genomes are unfinished due to the algorithmic challenges of assembling them. A variety of assembly and scaffolding tools are available, but it is not always obvious which tool or parameters to use for a specific genome size and complexity. It is, therefore, common practice to produce multiple assemblies using different assemblers and parameters, then select the best one for public release. A more compelling approach would allow one to merge multiple assemblies with the intent of producing a higher quality consensus assembly, which is the objective of assembly reconciliation. Several assembly reconciliation tools have been proposed in the literature, but their strengths and weaknesses have never been compared on a common dataset. We fill this need with this work, in which we report on an extensive comparative evaluation of several tools. Specifically, we evaluate contiguity, correctness, coverage, and the duplication ratio of the merged assembly compared to the individual assemblies provided as input. None of the tools we tested consistently improved the quality of the input GAGE and synthetic assemblies. Our experiments show an increase in contiguity in the consensus assembly when the original assemblies already have high quality. In terms of correctness, the quality of the results depends on the specific tool, as well as on the quality and the ranking of the input assemblies. In general, the number of misassemblies ranges from being comparable to the best of the input assembly to being comparable to the worst of the input assembly.

Nondestructive evaluation of loose assemblies using multi-frequency eddy currents and artificial neural networks

International Nuclear Information System (INIS)

Vourc’h, Eric; Le Gac, Guillaume; Larzabal, Pascal; Joubert, Pierre-Yves

2013-01-01

This paper considers the problem of the evaluation of metallic assemblies in an aeronautical context, by means of a non-invasive method. The problems lies in the estimation of the distance separating two aluminum plates representative of a loose assembly (up to 300 µm), the top plate being possibly of unknown thickness ranging from 1 to 8 mm. To do so, the eddy current (EC) method is chosen, because it allows non-contact evaluation of conducting media to be carried out, which is sensitive to electrical conductivity changes in the part under evaluation, and hence to the presence of an air gap between parts. The problem falls into the category of evaluation of a multilayered conductive structure starting from EC data, which is an ill-posed problem. In order to bypass these difficulties, as well as to deal with the uncertainties that may be introduced by the experimental set-up, a ‘non-model’ approach is implemented by means of an artificial neural network (ANN). The latter is elaborated in a statistical learning approach starting from the experimental EC data provided by a ferrite cored coil EC probe used to investigate an assembly mockup of adjustable configuration. Moreover, in order to build a learning database allowing a robust and accurate ANN to be elaborated, as well as to deal with assemblies of unknown thicknesses, we consider EC data obtained at different frequencies chosen in an adjusted frequency bandwidth, experimentally determined so as to optimize the sensitivity toward the presence of an air gap between parts. The implementation of the proposed approach for distances between parts ranging from 60 to 300 µm provided estimated root mean square errors ranging from 7 μm up to 50 µm for the estimation of the distance between parts, and ranging from 20 µm up to 1.4 mm for the estimation of the top plates, ranging from 1 to 8 mm, respectively. (paper)

Magnetic scanning of LWR fuel assemblies

International Nuclear Information System (INIS)

Fiarman, S.; Moodenbaugh, A.

1980-01-01

Nondestructive assay (NDA) techniques are available both for fresh and spent fuel, but generally are too time consuming and do not uniquely identify an assembly. A new method is reported to obtain a signature from a magnetic scan of each assembly. This scan is an NDA technique that detects magnetic inclusions. It is potentially fast (5 min/assembly), and may provide a unique signature from the magnetic properties of each fuel assembly

A highly flexible platform for nanowire sensor assembly using a combination of optically induced and conventional dielectrophoresis.

Science.gov (United States)

Lin, Yen-Heng; Ho, Kai-Siang; Yang, Chin-Tien; Wang, Jung-Hao; Lai, Chao-Sung

2014-06-02

The number and position of assembled nanowires cannot be controlled using most nanowire sensor assembling methods. In this paper, we demonstrate a high-yield, highly flexible platform for nanowire sensor assembly using a combination of optically induced dielectrophoresis (ODEP) and conventional dielectrophoresis (DEP). With the ODEP platform, optical images can be used as virtual electrodes to locally turn on a non-contact DEP force and manipulate a micron- or nano-scale substance suspended in fluid. Nanowires were first moved next to the previously deposited metal electrodes using optical images and, then, were attracted to and arranged in the gap between two electrodes through DEP forces generated by switching on alternating current signals to the metal electrodes. A single nanowire can be assembled within 24 seconds using this approach. In addition, the number of nanowires in a single nanowire sensor can be controlled, and the assembly of a single nanowire on each of the adjacent electrodes can also be achieved. The electrical properties of the assembled nanowires were characterized by IV curve measurement. Additionally, the contact resistance between the nanowires and electrodes and the stickiness between the nanowires and substrates were further investigated in this study.

QUAST: quality assessment tool for genome assemblies.

Science.gov (United States)

Gurevich, Alexey; Saveliev, Vladislav; Vyahhi, Nikolay; Tesler, Glenn

2013-04-15

Limitations of genome sequencing techniques have led to dozens of assembly algorithms, none of which is perfect. A number of methods for comparing assemblers have been developed, but none is yet a recognized benchmark. Further, most existing methods for comparing assemblies are only applicable to new assemblies of finished genomes; the problem of evaluating assemblies of previously unsequenced species has not been adequately considered. Here, we present QUAST-a quality assessment tool for evaluating and comparing genome assemblies. This tool improves on leading assembly comparison software with new ideas and quality metrics. QUAST can evaluate assemblies both with a reference genome, as well as without a reference. QUAST produces many reports, summary tables and plots to help scientists in their research and in their publications. In this study, we used QUAST to compare several genome assemblers on three datasets. QUAST tables and plots for all of them are available in the Supplementary Material, and interactive versions of these reports are on the QUAST website. http://bioinf.spbau.ru/quast . Supplementary data are available at Bioinformatics online.

Graphene growth by conversion of aromatic self-assembled monolayers

Energy Technology Data Exchange (ETDEWEB)

Turchanin, Andrey [Institute of Physical Chemistry, Friedrich Schiller University Jena (Germany); Jena Center for Soft Matter (JCSM), Jena (Germany); Center for Energy and Environmental Chemistry Jena (CEEC), Jena (Germany); Abbe Center of Photonics (ACP), Jena (Germany)

2017-11-15

Despite present diversity of graphene production methods there is still a high demand for improvement of the existing production schemes or development of new. Here a method is reviewed to produce graphene employing aromatic self-assembled monolayers (SAMs) as molecular precursors. This method is based on electron irradiation induced crosslinking of aromatic SAMs resulting in their conversion into carbon nanomembranes (CNMs) with high thermal stability and subsequent pyrolysis of CNMs into graphene in vacuum or in the inert atmosphere. Depending on the production conditions, such as chemical structure of molecular precursors, irradiation and annealing parameters, various properties of the produced graphene sheets including shape, crystallinity, thickness, optical properties and electric transport can be adjusted. The assembly of CNM/graphene van der Waals heterostructures opens a flexible route to non-destructive chemical functionalization of graphene for a variety of applications in electronic and photonic devices. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Self-assembly of a double-helical complex of sodium.

Science.gov (United States)

Bell, T W; Jousselin, H

1994-02-03

Spontaneous self-organization of helical and multiple-helical molecular structures occurs on several levels in living organisms. Key examples are alpha-helical polypeptides, double-helical nucleic acids and helical protein structures, including F-actin, microtubules and the protein sheath of the tobacco mosaic virus. Although the self-assembly of double-helical transition-metal complexes bears some resemblance to the molecular organization of double-stranded DNA, selection between monohelical, double-helical and triple-helical structures is determined largely by the size and geometrical preference of the tightly bound metal. Here we present an example of double-helical assembly induced by the weaker and non-directional interactions of an alkali-metal ion with an organic ligand that is pre-organized into a coil. We have characterized the resulting complex by two-dimensional NMR and fast-atom-bombardment mass spectrometry. These results provide a step toward the creation of molecular tubes or ion channels consisting of intertwined coils.

Power module assembly

Science.gov (United States)

Campbell, Jeremy B [Torrance, CA; Newson, Steve [Redondo Beach, CA

2011-11-15

A power module assembly of the type suitable for deployment in a vehicular power inverter, wherein the power inverter has a grounded chassis, is provided. The power module assembly comprises a conductive base layer electrically coupled to the chassis, an insulating layer disposed on the conductive base layer, a first conductive node disposed on the insulating layer, a second conductive node disposed on the insulating layer, wherein the first and second conductive nodes are electrically isolated from each other. The power module assembly also comprises a first capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the first conductive node, and further comprises a second capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the second conductive node.

Method of transporting fuel assemblies

International Nuclear Information System (INIS)

Okada, Katsutoshi.

1979-01-01

Purpose: To enable safety transportation of fuel assemblies for FBR type reactors by surrounding each of fuel elements in a wrapper tube by a rubbery, hollow cylindrical container and by sealing medium such as air to the inside of the container. Method: A fuel element is contained in a hollow cylindrical rubber-like tube. The fuel element has an upper end plug, a lower end plug and a wire spirally wound around the outer periphery. Upon transportation of the fuel assemblies, each of the fuel elements is covered with the container and arranged in the wrapper tube and then the fuel assemblies are assembled. Then, medium such as air is sealed for each of the fuel elements by way of an opening and then the opening is tightly closed. Before loading the transported fuel assemblies in the reactor, the medium is discharged through the opening and the container is completely extracted and removed from the inside of the wrapper tube. (Seki, T.)

Modular fuel-cell stack assembly

Science.gov (United States)

Patel, Pinakin

2010-07-13

A fuel cell assembly having a plurality of fuel cells arranged in a stack. An end plate assembly abuts the fuel cell at an end of said stack. The end plate assembly has an inlet area adapted to receive an exhaust gas from the stack, an outlet area and a passage connecting the inlet area and outlet area and adapted to carry the exhaust gas received at the inlet area from the inlet area to the outlet area. A further end plate assembly abuts the fuel cell at a further opposing end of the stack. The further end plate assembly has a further inlet area adapted to receive a further exhaust gas from the stack, a further outlet area and a further passage connecting the further inlet area and further outlet area and adapted to carry the further exhaust gas received at the further inlet area from the further inlet area to the further outlet area.

Nuclear reactor spacer assembly

International Nuclear Information System (INIS)

Anthony, A.J.; Groves, M.D.

1979-01-01

A fuel assembly for a nuclear reactor is disclosed wherein the fuel element receiving and supporting grid is comprised of a first metal, the guide tubes which pass through the grid assembly are comprised of a second metal and the grid is supported on the guide tubes by means of expanded sleeves located intermediate the grid and guide tubes. The fuel assembly is fabricated by inserting the sleeves, of initial outer diameter commensurate with the guide tube outer diameters, through the holes in the grid assembly provided for the guide tubes and thereafter expanding the sleeves radially outwardly along their entire length such that the guide tubes can subsequently be passed through the sleeves. The step of radial expansion, as a result of windows provided in the sleeves having dimensions commensurate with the geometry of the grid, mechanically captures the grid and simultaneously preloads the sleeve against the grid whereby relative motion between the grid and guide tube will be precluded

Automated ensemble assembly and validation of microbial genomes

Science.gov (United States)

2014-01-01

Background The continued democratization of DNA sequencing has sparked a new wave of development of genome assembly and assembly validation methods. As individual research labs, rather than centralized centers, begin to sequence the majority of new genomes, it is important to establish best practices for genome assembly. However, recent evaluations such as GAGE and the Assemblathon have concluded that there is no single best approach to genome assembly. Instead, it is preferable to generate multiple assemblies and validate them to determine which is most useful for the desired analysis; this is a labor-intensive process that is often impossible or unfeasible. Results To encourage best practices supported by the community, we present iMetAMOS, an automated ensemble assembly pipeline; iMetAMOS encapsulates the process of running, validating, and selecting a single assembly from multiple assemblies. iMetAMOS packages several leading open-source tools into a single binary that automates parameter selection and execution of multiple assemblers, scores the resulting assemblies based on multiple validation metrics, and annotates the assemblies for genes and contaminants. We demonstrate the utility of the ensemble process on 225 previously unassembled Mycobacterium tuberculosis genomes as well as a Rhodobacter sphaeroides benchmark dataset. On these real data, iMetAMOS reliably produces validated assemblies and identifies potential contamination without user intervention. In addition, intelligent parameter selection produces assemblies of R. sphaeroides comparable to or exceeding the quality of those from the GAGE-B evaluation, affecting the relative ranking of some assemblers. Conclusions Ensemble assembly with iMetAMOS provides users with multiple, validated assemblies for each genome. Although computationally limited to small or mid-sized genomes, this approach is the most effective and reproducible means for generating high-quality assemblies and enables users to

Storage arrangement for nuclear reactor fuel assemblies

International Nuclear Information System (INIS)

Wade, E.E.

1977-01-01

Said invention is intended for providing an arrangement of spent fuel assembly storage inside which the space is efficiently used without accumulating a critical mass. The storage is provided for long fuel assemblies having along their longitudinal axis an active part containing the fuel and an inactive part empty of fuel. Said storage arrangement comprises a framework constituting some long-shaped cells designed so as each of them can receive a fuel assembly. Means of axial positioning of said assembly in a cell make it possible to support the fuel assemblies inside the framework according to a spacing ratio, along the cell axis, such as the active part of an assembly is adjacent to the inactive part of the adjacent assemblies [fr

Integral nuclear fuel element assembly

International Nuclear Information System (INIS)

Schluderberg, D. C.

1985-01-01

An integral nuclear fuel element assembly utilizes longitudinally finned fuel pins. The continuous or interrupted fins of the fuel pins are brazed to fins of juxtaposed fuel pins or directly to the juxtaposed fuel pins or both. The integrally brazed fuel assembly is designed to satisfy the thermal and hydraulic requirements of a fuel assembly lattice having moderator to fuel atom ratios required to achieve high conversion and breeding ratios

Centrioles: Some Self-Assembly Required

OpenAIRE

Song, Mi Hye; Miliaras, Nicholas B.; Peel, Nina; O'Connell, Kevin F.

2008-01-01

Centrioles play an important role in organizing microtubules and are precisely duplicated once per cell cycle. New (daughter) centrioles typically arise in association with existing (mother) centrioles (canonical assembly), suggesting that mother centrioles direct the formation of daughter centrioles. However, under certain circumstances, centrioles can also self-assemble free of an existing centriole (de novo assembly). Recent work indicates that the canonical and de novo pathways utilize a ...

Manufacturing requirements of reactor assembly components for PFBR (Paper No. 041)

International Nuclear Information System (INIS)

Murty, C.G.K.; Bhoje, S.B.

1987-02-01

This paper enumerates the requirements of 500 MWe Prototype Fast Breeder Reactor (PFBR) components and considering the present state of art of Indian industry an analysis is made on the challenges to be faced in manufacture highlighting the areas needing development. The large sizes and weights of the components coupled with the limitations on shop facilities and ODC transport, demand part of the fabrication to be done at shop and balance assembly work as well as certain assembly machining operations to be done at site work shop. The stringent geometrical tolerances coupled with extensive destructive and non-destructive examinations call for balanced and low heat input welding techniques and special inspection equipment like electronic co-ordinate determination system. The present paper deals with the specific manufacturing problems of the main reactor components. (author)

Doxycycline hinders phenylalanine fibril assemblies revealing a potential novel therapeutic approach in phenylketonuria.

Science.gov (United States)

De Luigi, Ada; Mariani, Alessandro; De Paola, Massimiliano; Re Depaolini, Andrea; Colombo, Laura; Russo, Luca; Rondelli, Valeria; Brocca, Paola; Adler-Abramovich, Lihi; Gazit, Ehud; Del Favero, Elena; Cantù, Laura; Salmona, Mario

2015-10-29

A new paradigm for the aetiopathology of phenylketonuria suggests the presence of amyloid-like assemblies in the brains of transgenic mouse models and patients with phenylketonuria, possibly shedding light on the selective cognitive deficit associated with this disease. Paralleling the amyloidogenic route that identifies different stages of peptide aggregation, corresponding to different levels of toxicity, we experimentally address for the first time, the physico-chemical properties of phenylalanine aggregates via Small Angle, Wide Angle X-ray Scattering and Atomic Force Microscopy. Results are consistent with the presence of well-structured, aligned fibres generated by milliMolar concentrations of phenylalanine. Moreover, the amyloid-modulating doxycycline agent affects the local structure of phenylalanine aggregates, preventing the formation of well-ordered crystalline structures. Phenylalanine assemblies prove toxic in vitro to immortalized cell lines and primary neuronal cells. Furthermore, these assemblies also cause dendritic sprouting alterations and synaptic protein impairment in neurons. Doxycycline counteracts these toxic effects, suggesting an approach for the development of future innovative non-dietary preventive therapies.

Conformal dip-coating of patterned surfaces for capillary die-to-substrate self-assembly

International Nuclear Information System (INIS)

Mastrangeli, M; Ruythooren, W; Van Hoof, C; Celis, J-P

2009-01-01

Capillarity-driven self-assembly of small chips onto planar target substrates is a promising alternative to robotic pick-and-place assembly. It critically relies on the selective deposition of thin fluid films on patterned binding sites, which is anyway normally non-conformal. We found that the addition of a thin wetting sidewall, surrounding the entire site perimeter, enables the conformal fluid coverage of arbitrarily shaped sites through dip-coating, significantly improves the reproducibility of the coating process and strongly reduces its sensitivity to surface defects. In this paper we support the feasibility and potential of this method by demonstrating the conformal dip-coating of square and triangular sites conditioned with combinations of different hydrophobic and hydrophilic surface chemistries. We present both experimental and simulative evidence of the advantages brought by the introduction of the wetting boundary on film coverage accuracy. Application of our surface preparation method to capillary self-assembly could result in higher precision in die-to-substrate registration and larger freedom in site shape design

Peculiarities of the Assembling Structure of the Novel "Shaved Man" by A. Marienhof

Directory of Open Access Journals (Sweden)

Ekaterina Yu. Belash

2017-03-01

Full Text Available The article analyzes the characteristics of various embodiments of assembling techniques in the context of the narrative structure of the novel by A. Marienhof «The shaved man». The writer’s prose is distinguished by the non-linearity of the composition and the fragmentation of the text. Great influence on the work of the author made the art of cinema that was actively developed in the early XX century. The novel «The shaved man» is a kind of game, and a continuous experiment with various techniques of installation proposed by S. Eisenstein, L. Kuleshov, Pudovkin, etc. Within this text it is enumerated not only the main assembling methods, but also revealed the specifics of their influence on the formation of various meanings. Thanks to the assembling of heterogeneous and diverse objects Marienhof managed to portray in detail both the fate of the characters and the history of the turning epoch the early XX century as a whole.

Non_standard Wood

DEFF Research Database (Denmark)

Tamke, Martin

. Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software......, but the integration of traditional wood craft techniques. The extensive use of self adjusting, load bearing wood-wood joints contributed to ease in production and assembly of a performance based architecture....

Assembly of the PLT device

International Nuclear Information System (INIS)

Marino, R.

1975-11-01

The assembly of the PLT device began in June 1974 with a preassembly of the mechanical structure at a remote site. The preassembly sequence incorporated final fabrication procedures with an initial staging operation. This successful staging/fabrication procedure proved to be an invaluable asset when the final assembly was started in August 1974. The assembly continued with the initial reassembly of the previously tested structural components at the final machine site. Construction was interrupted at several points to allow for toroidal field coil, vacuum vessel, and poloidal coil installation. Two phases of toroidal field coil power tests were included in the assembly sequence prior to, and just after the vacuum vessel insertion

PAVE: Program for assembling and viewing ESTs

Directory of Open Access Journals (Sweden)

Bomhoff Matthew

2009-08-01

Full Text Available Abstract Background New sequencing technologies are rapidly emerging. Many laboratories are simultaneously working with the traditional Sanger ESTs and experimenting with ESTs generated by the 454 Life Science sequencers. Though Sanger ESTs have been used to generate contigs for many years, no program takes full advantage of the 5' and 3' mate-pair information, hence, many tentative transcripts are assembled into two separate contigs. The new 454 technology has the benefit of high-throughput expression profiling, but introduces time and space problems for assembling large contigs. Results The PAVE (Program for Assembling and Viewing ESTs assembler takes advantage of the 5' and 3' mate-pair information by requiring that the mate-pairs be assembled into the same contig and joined by n's if the two sub-contigs do not overlap. It handles the depth of 454 data sets by "burying" similar ESTs during assembly, which retains the expression level information while circumventing time and space problems. PAVE uses MegaBLAST for the clustering step and CAP3 for assembly, however it assembles incrementally to enforce the mate-pair constraint, bury ESTs, and reduce incorrect joins and splits. The PAVE data management system uses a MySQL database to store multiple libraries of ESTs along with their metadata; the management system allows multiple assemblies with variations on libraries and parameters. Analysis routines provide standard annotation for the contigs including a measure of differentially expressed genes across the libraries. A Java viewer program is provided for display and analysis of the results. Our results clearly show the benefit of using the PAVE assembler to explicitly use mate-pair information and bury ESTs for large contigs. Conclusion The PAVE assembler provides a software package for assembling Sanger and/or 454 ESTs. The assembly software, data management software, Java viewer and user's guide are freely available.

PAVE: program for assembling and viewing ESTs.

Science.gov (United States)

Soderlund, Carol; Johnson, Eric; Bomhoff, Matthew; Descour, Anne

2009-08-26

New sequencing technologies are rapidly emerging. Many laboratories are simultaneously working with the traditional Sanger ESTs and experimenting with ESTs generated by the 454 Life Science sequencers. Though Sanger ESTs have been used to generate contigs for many years, no program takes full advantage of the 5' and 3' mate-pair information, hence, many tentative transcripts are assembled into two separate contigs. The new 454 technology has the benefit of high-throughput expression profiling, but introduces time and space problems for assembling large contigs. The PAVE (Program for Assembling and Viewing ESTs) assembler takes advantage of the 5' and 3' mate-pair information by requiring that the mate-pairs be assembled into the same contig and joined by n's if the two sub-contigs do not overlap. It handles the depth of 454 data sets by "burying" similar ESTs during assembly, which retains the expression level information while circumventing time and space problems. PAVE uses MegaBLAST for the clustering step and CAP3 for assembly, however it assembles incrementally to enforce the mate-pair constraint, bury ESTs, and reduce incorrect joins and splits. The PAVE data management system uses a MySQL database to store multiple libraries of ESTs along with their metadata; the management system allows multiple assemblies with variations on libraries and parameters. Analysis routines provide standard annotation for the contigs including a measure of differentially expressed genes across the libraries. A Java viewer program is provided for display and analysis of the results. Our results clearly show the benefit of using the PAVE assembler to explicitly use mate-pair information and bury ESTs for large contigs. The PAVE assembler provides a software package for assembling Sanger and/or 454 ESTs. The assembly software, data management software, Java viewer and user's guide are freely available.

Technical operations procedure for assembly and emplacement of the soil temperature test--test assembly

International Nuclear Information System (INIS)

Weber, A.P.

1978-01-01

A description is given of the plan for assembly, instrumentation, emplacement, and operational checkout of the soil temperature test assembly and dry well liner. The activities described cover all operations necessary to accomplish the receiving inspection, instrumentation and pre-construction handling of the dry well liner, plus all operations performed with the test article. Actual details of construction work are not covered by this procedure. Each part and/or section of this procedure is a separate function to be accomplished as required by the nature of the operation. The organization of the procedure is not intended to imply a special operational sequence or schedular requirement. Specific procedure operational sections include: receiving inspection; liner assembly operations; construction operations (by others); prepare shield plug; test article assembly and installation; and operational checkout

Transfer of fuel assemblies

International Nuclear Information System (INIS)

Vuckovich, M.; Burkett, J. P.; Sallustio, J.

1984-01-01

Fuel assemblies of a nuclear reactor are transferred during fueling or refueling or the like by a crane. The work-engaging fixture of the crane picks up an assembly, removes it from this slot, transfers it to the deposit site and deposits it in its slot at the deposit site. The control for the crane includes a strain gauge connected to the crane line which raises and lowers the load. The strain gauge senses the load on the crane. The signal from the strain gauge is compared with setpoints; a high-level setpoint, a low-level setpoint and a slack-line setpoint. If the strain gauge signal exceeds the high-level setpoint, the line drive is disabled. This event may occur during raising of a fuel assembly which encounters resistance. The high-level setpoint may be overridden under proper precautions. The line drive is also disabled if the strain gauge signal is less than the low-level setpoint. This event occurs when a fuel assembly being deposited contacts the bottom of its slot or an obstruction in, or at the entry to the slot. To preclude lateral movement and possible damage to a fuel assembly suspended from the crane line, the traverse drive of the crane is disabled once the strain-gauge exceets the lov-level setpoint. The traverse drive can only be enabled after the strain-gauge signal is less than the slack-line set-point. This occurs when the lines has been set in slack-line setting. When the line is tensioned after slack-li ne setting, the traverse drive remains enabled only if the line has been disconnected from the fuel assembly

Improvements in nuclear fuel assembly sleeves

International Nuclear Information System (INIS)

Eaton, C.W.; Seeley, T.A.; Ince, G.; Speakman, W.T.

1986-01-01

The graphite sleeve of a nuclear fuel assembly or reflector element for a stringer mounts a number of grids via mounting assemblies installed in grooves formed in the interior wall surface of the sleeve. The bore of the sleeve is of reduced cross-section between two successive grooves such that the internal diameter of the sleeve is substantially the same as the inner diameter of the radially innermost extremity of the mounting assemblies whereby the coolant pressure loss at each transition between the reduced diameter bore section and the mounting assemblies is reduced. Each mounting assembly may be of radially contractable split ring construction to permit its placement in the groove and may carry burnable poison material. (author)

Improvements in nuclear fuel assembly sleeves

Energy Technology Data Exchange (ETDEWEB)

Eaton, C.W.; Seeley, T.A.; Ince, G.; Speakman, W.T.

1986-02-26

The graphite sleeve of a nuclear fuel assembly or reflector element for a stringer mounts a number of grids via mounting assemblies installed in grooves formed in the interior wall surface of the sleeve. The bore of the sleeve is of reduced cross-section between two successive grooves such that the internal diameter of the sleeve is substantially the same as the inner diameter of the radially innermost extremity of the mounting assemblies whereby the coolant pressure loss at each transition between the reduced diameter bore section and the mounting assemblies is reduced. Each mounting assembly may be of radially contractable split ring construction to permit its placement in the groove and may carry burnable poison material.

Physical principles for DNA tile self-assembly.

Science.gov (United States)

Evans, Constantine G; Winfree, Erik

2017-06-19

DNA tiles provide a promising technique for assembling structures with nanoscale resolution through self-assembly by basic interactions rather than top-down assembly of individual structures. Tile systems can be programmed to grow based on logical rules, allowing for a small number of tile types to assemble large, complex assemblies that can retain nanoscale resolution. Such algorithmic systems can even assemble different structures using the same tiles, based on inputs that seed the growth. While programming and theoretical analysis of tile self-assembly often makes use of abstract logical models of growth, experimentally implemented systems are governed by nanoscale physical processes that can lead to very different behavior, more accurately modeled by taking into account the thermodynamics and kinetics of tile attachment and detachment in solution. This review discusses the relationships between more abstract and more physically realistic tile assembly models. A central concern is how consideration of model differences enables the design of tile systems that robustly exhibit the desired abstract behavior in realistic physical models and in experimental implementations. Conversely, we identify situations where self-assembly in abstract models can not be well-approximated by physically realistic models, putting constraints on physical relevance of the abstract models. To facilitate the discussion, we introduce a unified model of tile self-assembly that clarifies the relationships between several well-studied models in the literature. Throughout, we highlight open questions regarding the physical principles for DNA tile self-assembly.

Assembly of cell-laden hydrogel fiber into non-liquefied and liquefied 3D spiral constructs by perfusion-based layer-by-layer technique

International Nuclear Information System (INIS)

Sher, Praveen; Oliveira, Sara M; Borges, João; Mano, João F

2015-01-01

In this work, three-dimensional (3D) self-sustaining, spiral-shaped constructs were produced through a combination of ionotropic gelation, to form cell-encapsulated alginate fibers, and a perfusion-based layer-by-layer (LbL) technique. Single fibers were assembled over cylindrical molds by reeling to form spiral shapes, both having different geometries and sizes. An uninterrupted nanometric multilayer coating produced by a perfusion-based LbL technique, using alginate and chitosan, generated stable 3D spiral-shaped macrostructures by gripping and affixing the threads together without using any crosslinking/binding agent. The chelation process altered the internal microenvironment of the 3D construct from the solid to the liquefied state while preserving the external geometry. L929 cell viability by MTS and dsDNA quantification favor liquefied 3D constructs more than non-liquefied ones. The proposed technique setup helps us to generate complex polyelectrolyte-based 3D constructs for tissue engineering applications and organ printing. (note)

Optimizing and benchmarking de novo transcriptome sequencing: from library preparation to assembly evaluation.

Science.gov (United States)

Hara, Yuichiro; Tatsumi, Kaori; Yoshida, Michio; Kajikawa, Eriko; Kiyonari, Hiroshi; Kuraku, Shigehiro

2015-11-18

RNA-seq enables gene expression profiling in selected spatiotemporal windows and yields massive sequence information with relatively low cost and time investment, even for non-model species. However, there remains a large room for optimizing its workflow, in order to take full advantage of continuously developing sequencing capacity. Transcriptome sequencing for three embryonic stages of Madagascar ground gecko (Paroedura picta) was performed with the Illumina platform. The output reads were assembled de novo for reconstructing transcript sequences. In order to evaluate the completeness of transcriptome assemblies, we prepared a reference gene set consisting of vertebrate one-to-one orthologs. To take advantage of increased read length of >150 nt, we demonstrated shortened RNA fragmentation time, which resulted in a dramatic shift of insert size distribution. To evaluate products of multiple de novo assembly runs incorporating reads with different RNA sources, read lengths, and insert sizes, we introduce a new reference gene set, core vertebrate genes (CVG), consisting of 233 genes that are shared as one-to-one orthologs by all vertebrate genomes examined (29 species)., The completeness assessment performed by the computational pipelines CEGMA and BUSCO referring to CVG, demonstrated higher accuracy and resolution than with the gene set previously established for this purpose. As a result of the assessment with CVG, we have derived the most comprehensive transcript sequence set of the Madagascar ground gecko by means of assembling individual libraries followed by clustering the assembled sequences based on their overall similarities. Our results provide several insights into optimizing de novo RNA-seq workflow, including the coordination between library insert size and read length, which manifested in improved connectivity of assemblies. The approach and assembly assessment with CVG demonstrated here would be applicable to transcriptome analysis of other species as

System for assembling nuclear fuel elements

International Nuclear Information System (INIS)

1980-01-01

An automatic system is described for assembling nuclear fuel elements, in particular those employing mixed oxide fuels. The system includes a sealing mechanism which allows movement during the assembling of the fuel element along the assembly stations without excessive release of contaminants. (U.K.)

Assembly study for JT-60SA tokamak

Energy Technology Data Exchange (ETDEWEB)

Shibanuma, K., E-mail: shibanuma.kiyoshi@jaea.go.jp [Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan); Arai, T.; Hasegawa, K.; Hoshi, R.; Kamiya, K.; Kawashima, H.; Kubo, H.; Masaki, K.; Saeki, H.; Sakurai, S.; Sakata, S.; Sakasai, A.; Sawai, H.; Shibama, Y.K.; Tsuchiya, K.; Tsukao, N.; Yagyu, J.; Yoshida, K.; Kamada, Y. [Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan); Mizumaki, S. [Toshiba Corporation, Minato-ku, Tokyo 105-8001 (Japan); and others

2013-10-15

The assembly scenarios and assembly tools of the major tokamak components for JT-60SA are studied in the following. (1) The assembly frame (with a dedicated 30-tonne crane), which is located around the JT-60SA tokamak, is adopted for effective assembly works in the torus hall and the temporary support of the components during assembly. (2) Metrology for precise positioning of the components is also studied by defining the metrology points on the components. (3) The sector segmentation for weld joints and positioning of the vacuum vessel (VV), the assembly scenario and tools for VV thermal shield (TS), the connection of the outer intercoil structure (OIS) and the installation of the final toroidal field coil (TFC) are studied, as typical examples of the assembly scenarios and tools for JT-60SA.

Self-assembly of Polystyrene- b -poly(2-vinylpyridine)- b -poly(ethylene oxide) Triblock Terpolymers

KAUST Repository

Musteata, Valentina-Elena; Sutisna, Burhannudin; Polymeropoulos, Georgios; Avgeropoulos, Apostolos; Meneau, Florian; Peinemann, Klaus-Viktor; Hadjichristidis, Nikolaos; Nunes, Suzana Pereira

2017-01-01

Polystyrene-b-poly(2-vinylpyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO) terpolymer is a versatile polymer to form isoporous films and membranes, due to the possibility of self-assembly control and the properties of the different blocks, such as the P2VP ability of complexation, and H-bond formation, and the PEO biocompatibility. Copolymers with different block ratios and sizes were synthesized. The correlation between their equilibrium bulk morphology, the self-assembly in dilute and semi-dilute solutions and the non-equilibrium porous structures of membranes, obtained by non-solvent induced phase separation, was investigated and discussed in detail. The characterization was performed by small-angle X-ray scattering (SAXS), scanning (SEM) and transmission electron microscopy (TEM). Hexagonal, cubic and lamellar arrangements were observed. The preparation conditions were optimized and a regular, isoporous morphology, suitable for membrane application, was successfully obtained with PS80.5k-b-P2VP64.4k-b-PEO16.1k.

Self-assembly of Polystyrene- b -poly(2-vinylpyridine)- b -poly(ethylene oxide) Triblock Terpolymers

KAUST Repository

Musteata, Valentina-Elena

2017-11-08

Polystyrene-b-poly(2-vinylpyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO) terpolymer is a versatile polymer to form isoporous films and membranes, due to the possibility of self-assembly control and the properties of the different blocks, such as the P2VP ability of complexation, and H-bond formation, and the PEO biocompatibility. Copolymers with different block ratios and sizes were synthesized. The correlation between their equilibrium bulk morphology, the self-assembly in dilute and semi-dilute solutions and the non-equilibrium porous structures of membranes, obtained by non-solvent induced phase separation, was investigated and discussed in detail. The characterization was performed by small-angle X-ray scattering (SAXS), scanning (SEM) and transmission electron microscopy (TEM). Hexagonal, cubic and lamellar arrangements were observed. The preparation conditions were optimized and a regular, isoporous morphology, suitable for membrane application, was successfully obtained with PS80.5k-b-P2VP64.4k-b-PEO16.1k.

Improving transcriptome construction in non-model organisms: integrating manual and automated gene definition in Emiliania huxleyi.

OpenAIRE

Feldmesser, Ester; Rosenwasser, Shilo; Vardi, Assaf; Ben-Dor, Shifra

2014-01-01

Background The advent of Next Generation Sequencing technologies and corresponding bioinformatics tools allows the definition of transcriptomes in non-model organisms. Non-model organisms are of great ecological and biotechnological significance, and consequently the understanding of their unique metabolic pathways is essential. Several methods that integrate de novo assembly with genome-based assembly have been proposed. Yet, there are many open challenges in defining genes, particularly whe...

RCC-C: Design and construction rules for fuel assemblies of PWR nuclear power plants

International Nuclear Information System (INIS)

2015-01-01

The RCC-C code contains all the requirements for the design, fabrication and inspection of nuclear fuel assemblies and the different types of core components (rod cluster control assemblies, burnable poison rod assemblies, primary and secondary source assemblies and thimble plug assemblies). The design, fabrication and inspection rules defined in RCC-C leverage the results of the research and development work pioneered in France, Europe and worldwide, and which have been successfully used by industry to design and build nuclear fuel assemblies and incorporate the resulting feedback. The code's scope covers: fuel system design, especially for assemblies, the fuel rod and associated core components, the characteristics to be checked for products and parts, fabrication methods and associated inspection methods. The RCC-C code is used by the operator of the PWR nuclear power plants in France as a reference when sourcing fuel from the world's top two suppliers in the PWR market, given that the French operator is the world's largest buyer of PWR fuel. Fuel for EPR projects is manufactured according to the provisions of the RCC-C code. The code is available in French and English. The 2005 edition has been translated into Chinese. Contents of the 2015 edition of the RCC-C code: Chapter 1 - General provisions: 1.1 Purpose of the RCC-C, 1.2 Definitions, 1.3 Applicable standards, 1.4 Equipment subject to the RCC-C, 1.5 Management system, 1.6 Processing of non-conformances; Chapter 2 - Description of the equipment subject to the RCC-C: 2.1 Fuel assembly, 2.2 Core components; Chapter 3 - Design: Safety functions, operating functions and environment of fuel assemblies and core components, design and safety principles; Chapter 4 - Manufacturing: 4.1 Materials and part characteristics, 4.2 Assembly requirements, 4.3 Manufacturing and inspection processes, 4.4 Inspection methods, 4.5 Certification of NDT inspectors, 4.6 Characteristics to be inspected for the

Tunable porous nanoallotropes prepared by post-assembly etching of binary nanoparticle superlattices

Science.gov (United States)

Udayabhaskararao, Thumu; Altantzis, Thomas; Houben, Lothar; Coronado-Puchau, Marc; Langer, Judith; Popovitz-Biro, Ronit; Liz-Marzán, Luis M.; Vuković, Lela; Král, Petr; Bals, Sara; Klajn, Rafal

2017-10-01

Self-assembly of inorganic nanoparticles has been used to prepare hundreds of different colloidal crystals, but almost invariably with the restriction that the particles must be densely packed. Here, we show that non-close-packed nanoparticle arrays can be fabricated through the selective removal of one of two components comprising binary nanoparticle superlattices. First, a variety of binary nanoparticle superlattices were prepared at the liquid-air interface, including several arrangements that were previously unknown. Molecular dynamics simulations revealed the particular role of the liquid in templating the formation of superlattices not achievable through self-assembly in bulk solution. Second, upon stabilization, all of these binary superlattices could be transformed into distinct “nanoallotropes”—nanoporous materials having the same chemical composition but differing in their nanoscale architectures.

Bioorthogonal cyclization-mediated in situ self-assembly of small-molecule probes for imaging caspase activity in vivo

Science.gov (United States)

Ye, Deju; Shuhendler, Adam J.; Cui, Lina; Tong, Ling; Tee, Sui Seng; Tikhomirov, Grigory; Felsher, Dean W.; Rao, Jianghong

2014-06-01

Directed self-assembly of small molecules in living systems could enable a myriad of applications in biology and medicine, and already this has been used widely to synthesize supramolecules and nano/microstructures in solution and in living cells. However, controlling the self-assembly of synthetic small molecules in living animals is challenging because of the complex and dynamic in vivo physiological environment. Here we employ an optimized first-order bioorthogonal cyclization reaction to control the self-assembly of a fluorescent small molecule, and demonstrate its in vivo applicability by imaging caspase-3/7 activity in human tumour xenograft mouse models of chemotherapy. The fluorescent nanoparticles assembled in situ were imaged successfully in both apoptotic cells and tumour tissues using three-dimensional structured illumination microscopy. This strategy combines the advantages offered by small molecules with those of nanomaterials and should find widespread use for non-invasive imaging of enzyme activity in vivo.

Competition-colonization trade-offs, competitive uncertainty, and the evolutionary assembly of species.

Directory of Open Access Journals (Sweden)

Pradeep Pillai

Full Text Available We utilize a standard competition-colonization metapopulation model in order to study the evolutionary assembly of species. Based on earlier work showing how models assuming strict competitive hierarchies will likely lead to runaway evolution and self-extinction for all species, we adopt a continuous competition function that allows for levels of uncertainty in the outcome of competition. We then, by extending the standard patch-dynamic metapopulation model in order to include evolutionary dynamics, allow for the coevolution of species into stable communities composed of species with distinct limiting similarities. Runaway evolution towards stochastic extinction then becomes a limiting case controlled by the level of competitive uncertainty. We demonstrate how intermediate competitive uncertainty maximizes the equilibrium species richness as well as maximizes the adaptive radiation and self-assembly of species under adaptive dynamics with mutations of non-negligible size. By reconciling competition-colonization tradeoff theory with co-evolutionary dynamics, our results reveal the importance of intermediate levels of competitive uncertainty for the evolutionary assembly of species.

Design for Manufacture and Assembly for Product Development (Case study : Emergency Lamp)

Science.gov (United States)

Ngatilah, Y.; Pulansari, F.; Ernawati, Dira; Pujiastuti, C.; Parwati, C. I.; Prasetyo, B.

2018-01-01

Community needs that are not primary but important in everyday life are lights for lighting. State electricity company (PLN) is experiencing limitations in supplying electricity for this puIDRose. Therefore emergency lights (emergency lights) are already marketed in the community, which limited function only illuminate a very limited space. Therefore we developed the design of energy saving lamps using “Light Emitting Diode” (LED) which can illuminate the whole house as well as functioning as mobile phone charger (HP). The method used is Design for Manufacture and Assembly (DFMA), with the result of design development The percentage increase in assembly efficiency (E) is 0.01071 - 0.00645 = 0.00426 or = 39.76%. The decrease in material costs is IDR 234,000 - IDR 214,000 = IDR 20,000 or = 8.54% .Development design is received because of more assembly efficiency than the initial design. Power usage on previous products with series and designs of the original product can last only 4-5 hours non-stop, while the development of the design can survive 9-10 hours 2x more energy efficient.

Assemble-to-order systems: a review

NARCIS (Netherlands)

Atan, Z.; Ahmadi, T.; Stegehuis, C.; de Kok, A.G.; Adan, I.J.B.F.

2017-01-01

In this paper, we review the recent literature on assemble-to-order systems. Each assemble-to-order system consists of multiple components and end-products. The components are assembled into the end-products after information on customer demand is received but the decision on what components to

A conceptual design and structural stabilities of in-pit assembly tools for the completion of final sector assembly at tokamak hall

International Nuclear Information System (INIS)

Nam, K.O.; Park, H.K.; Kim, D.J.; Ahn, H.J.; Kim, K.K.; Im, K.; Shaw, R.

2010-01-01

The final assembly of main components of the International Thermonuclear Experimental Reactor (ITER) tokamak, Vacuum Vessel (VV) and Toroidal Field Coils (TFCs), is achieved by the sequential assembly of the nine sub-assembled 40 o sectors in tokamak pit. Each sub-assembled 40 o sector is composed of one VV 40 o sector, two TFCs, and in-between Vacuum Vessel Thermal Shield (VVTS) segments. Sub-assembly is carried out in the assembly building and then the sub-assembled sectors are transferred into tokamak pit, in sequence, to complete sector assembly. The role of in-pit assembly tool is to support and align the sub-assembled sectors in tokamak pit. It also plays the role of reference datum during assembly until the completion of main components assembly. Korea Domestic Agency (KO DA) has developed the conceptual design of most ITER purpose-built assembly tools under the collaboration with the ITER Organization. Among the conceptual designs carried out, this paper describes the function, the structure, the selected material and the design results of the in-pit assembly tools comprising central column, radial beams and their supports, TF inner supports and in-pit working floor. The results of structural analysis using ANSYS for the various loading cases are given as well. The resultant stresses and deflections turned out to fall within the allowable ranges.

Quantifying quality in DNA self-assembly

Science.gov (United States)

Wagenbauer, Klaus F.; Wachauf, Christian H.; Dietz, Hendrik

2014-01-01

Molecular self-assembly with DNA is an attractive route for building nanoscale devices. The development of sophisticated and precise objects with this technique requires detailed experimental feedback on the structure and composition of assembled objects. Here we report a sensitive assay for the quality of assembly. The method relies on measuring the content of unpaired DNA bases in self-assembled DNA objects using a fluorescent de-Bruijn probe for three-base ‘codons’, which enables a comparison with the designed content of unpaired DNA. We use the assay to measure the quality of assembly of several multilayer DNA origami objects and illustrate the use of the assay for the rational refinement of assembly protocols. Our data suggests that large and complex objects like multilayer DNA origami can be made with high strand integration quality up to 99%. Beyond DNA nanotechnology, we speculate that the ability to discriminate unpaired from paired nucleic acids in the same macromolecule may also be useful for analysing cellular nucleic acids. PMID:24751596

The MARVEL assembly for neutron multiplication

Energy Technology Data Exchange (ETDEWEB)

David L. Chichester; Mathew T. Kinlaw

2013-10-01

A new multiplying test assembly is under development at Idaho National Laboratory to support research, validation, evaluation, and learning. The item is comprised of three stacked, highly-enriched uranium (HEU) cylinders, each 11.4 cm in diameter and having a combined height of up to 11.7 cm. The combined mass of all three cylinders is 20.3 kg of HEU. Calculations for the bare configuration of the assembly indicate a multiplication level of >3.5 (keff=0.72). Reflected configurations of the assembly, using either polyethylene or tungsten, are possible and have the capability of raising the assembly's multiplication level to greater than 10. This paper describes simulations performed to assess the assembly's multiplication level under different conditions and describes the resources available at INL to support the use of these materials. We also describe some preliminary calculations and test activities using the assembly to study neutron multiplication.

The MARVEL assembly for neutron multiplication.

Science.gov (United States)

Chichester, David L; Kinlaw, Mathew T

2013-10-01

A new multiplying test assembly is under development at Idaho National Laboratory to support research, validation, evaluation, and learning. The item is comprised of three stacked, highly-enriched uranium (HEU) cylinders, each 11.4 cm in diameter and having a combined height of up to 11.7 cm. The combined mass of all three cylinders is 20.3 kg of HEU. Calculations for the bare configuration of the assembly indicate a multiplication level of >3.5 (k(eff)=0.72). Reflected configurations of the assembly, using either polyethylene or tungsten, are possible and have the capability of raising the assembly's multiplication level to greater than 10. This paper describes simulations performed to assess the assembly's multiplication level under different conditions and describes the resources available at INL to support the use of these materials. We also describe some preliminary calculations and test activities using the assembly to study neutron multiplication. Copyright © 2013 Elsevier Ltd. All rights reserved.

Elucidation of density profile of self-assembled sitosterol + oryzanol tubules with small-angle neutron scattering

NARCIS (Netherlands)

Bot, A.; Gilbert, E.P.; Bouwman, W.G.; Sawalha, H.I.M.; Adel, den R.; Garamus, V.M.; Venema, P.; Linden, van der E.; Flöter, E.

2012-01-01

Small-angle neutron scattering (SANS) experiments have been performed on self-assembled tubules of sitosterol and oryzanol in triglyceride oils to investigate details of their structure. Alternative organic phases (deuterated and non-deuterated decane, limonene, castor oil and eugenol) were used to

School Assemblies: The Lost Art.

Science.gov (United States)

Beach, Daniel R.

1979-01-01

Guidelines and suggestions are offered for successful school assemblies. The school assembly should be a positive event; an occasion for developing unity, group loyalty, and desirable audience habits. (Author/MLF)

Analysis of PWR assembly bow

International Nuclear Information System (INIS)

Fetterman, Robert J.; Franceschini, Fausto

2008-01-01

Excessive out of core assembly bow has been observed during refueling outages of certain PWRs. Assembly bow can take on a rather complex S-shape, and in other cases C-shape bow is prevalent. Concerns have been raised regarding the impact of the observed assembly bow on the in-core power distribution and the safety analyses supporting the plant operations. In response to these concerns, Westinghouse has developed a comprehensive analysis process for determining the effects of assembly bow on core power distributions and plant operating margins. This methodology has been applied to a particular reactor as part of an overall safety reanalysis completed in support of plant modifications. This paper provides a brief description of the methods used and a summary of the pertinent results. (authors)

Analysis of PWR assembly bow

Energy Technology Data Exchange (ETDEWEB)

Fetterman, Robert J.; Franceschini, Fausto [Westinghouse Electric Company LLC, Pittsburgh, PA (United States)

2008-07-01

Excessive out of core assembly bow has been observed during refueling outages of certain PWRs. Assembly bow can take on a rather complex S-shape, and in other cases C-shape bow is prevalent. Concerns have been raised regarding the impact of the observed assembly bow on the in-core power distribution and the safety analyses supporting the plant operations. In response to these concerns, Westinghouse has developed a comprehensive analysis process for determining the effects of assembly bow on core power distributions and plant operating margins. This methodology has been applied to a particular reactor as part of an overall safety reanalysis completed in support of plant modifications. This paper provides a brief description of the methods used and a summary of the pertinent results. (authors)

Label-free peptide aptamer based impedimetric biosensor for highly sensitive detection of TNT with a ternary assembly layer.

Science.gov (United States)

Li, Yanyan; Zhao, Manru; Wang, Haiyan

2017-11-01

We report a label-free peptide aptamer based biosensor for highly sensitive detection of TNT which was designed with a ternary assembly layer consisting of anti-TNT peptide aptamer (peptamer), dithiothreitol (DTT), and 6-mercaptohexanol (MCH), forming Au/peptamer-DTT/MCH. A linear relationship between the change in electron transfer resistance and the logarithm of the TNT concentration from 0.44 to 18.92 pM, with a detection limit of 0.15 pM, was obtained. In comparison, the detection limit of the aptasensor with a common binary assembly layer (Au/peptamer/MCH) was 0.15 nM. The remarkable improvement in the detection limit could be ascribed to the crucial role of the ternary assembly layer, providing an OH-richer hydrophilic environment and a highly compact surface layer with minimal surface defects, reducing the non-covalent binding (physisorption) of the peptamer and non-specific adsorption of TNT onto the electrode surface, leading to high sensitivity, and which can serve as a general sensing platform for the fabrication of other biosensors.

From NGS assembly challenges to instability of fungal mitochondrial genomes: A case study in genome complexity.

Science.gov (United States)

Misas, Elizabeth; Muñoz, José Fernando; Gallo, Juan Esteban; McEwen, Juan Guillermo; Clay, Oliver Keatinge

2016-04-01

The presence of repetitive or non-unique DNA persisting over sizable regions of a eukaryotic genome can hinder the genome's successful de novo assembly from short reads: ambiguities in assigning genome locations to the non-unique subsequences can result in premature termination of contigs and thus overfragmented assemblies. Fungal mitochondrial (mtDNA) genomes are compact (typically less than 100 kb), yet often contain short non-unique sequences that can be shown to impede their successful de novo assembly in silico. Such repeats can also confuse processes in the cell in vivo. A well-studied example is ectopic (out-of-register, illegitimate) recombination associated with repeat pairs, which can lead to deletion of functionally important genes that are located between the repeats. Repeats that remain conserved over micro- or macroevolutionary timescales despite such risks may indicate functionally or structurally (e.g., for replication) important regions. This principle could form the basis of a mining strategy for accelerating discovery of function in genome sequences. We present here our screening of a sample of 11 fully sequenced fungal mitochondrial genomes by observing where exact k-mer repeats occurred several times; initial analyses motivated us to focus on 17-mers occurring more than three times. Based on the diverse repeats we observe, we propose that such screening may serve as an efficient expedient for gaining a rapid but representative first insight into the repeat landscapes of sparsely characterized mitochondrial chromosomes. Our matching of the flagged repeats to previously reported regions of interest supports the idea that systems of persisting, non-trivial repeats in genomes can often highlight features meriting further attention. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modification and Assembly of a Versatile Lactonase for Bacterial Quorum Quenching

Directory of Open Access Journals (Sweden)

Melissa K. Rhoads

2018-02-01

Full Text Available This work sets out to provide a self-assembled biopolymer capsule activated with a multi-functional enzyme for localized delivery. This enzyme, SsoPox, which is a lactonase and phosphotriesterase, provides a means of interrupting bacterial communication pathways that have been shown to mediate pathogenicity. Here we demonstrate the capability to express, purify and attach SsoPox to the natural biopolymer chitosan, preserving its activity to “neutralize” long-chain autoinducer-1 (AI-1 communication molecules. Attachment is shown via non-specific binding and by engineering tyrosine and glutamine affinity ‘tags’ at the C-terminus for covalent linkage. Subsequent degradation of AI-1, in this case N-(3-oxododecanoyl-l-homoserine lactone (OdDHL, serves to “quench” bacterial quorum sensing (QS, silencing intraspecies communication. By attaching enzymes to pH-responsive chitosan that, in turn, can be assembled into various forms, we demonstrate device-based flexibility for enzyme delivery. Specifically, we have assembled quorum-quenching capsules consisting of an alginate inner core and an enzyme “decorated” chitosan shell that are shown to preclude bacterial QS crosstalk, minimizing QS mediated behaviors.

Impact analysis of spent fuel jacket assemblies

International Nuclear Information System (INIS)

Aramayo, G.A.

1994-01-01

As part of the analyses performed in support of the reracking of the High Flux Isotope Reactor pool, it became necessary to prove the structural integrity of the spent fuel jacket assemblies subjected to gravity drop that result from postulated accidents associated with the handling of these assemblies while submerged in the pool. The spent fuel jacket assemblies are an integral part of the reracking project, and serve to house fuel assemblies. The structure integrity of the jacket assemblies from loads that result from impact from a height of 10 feet onto specified targets has been performed analytically using the computer program LS-DYNA3D. Nine attitudes of the assembly at the time of impact have been considered. Results of the analyses show that there is no failure of the assemblies as a result of the impact scenarios considered

Genome Sequence Databases (Overview): Sequencing and Assembly

Energy Technology Data Exchange (ETDEWEB)

Lapidus, Alla L.

2009-01-01

From the date its role in heredity was discovered, DNA has been generating interest among scientists from different fields of knowledge: physicists have studied the three dimensional structure of the DNA molecule, biologists tried to decode the secrets of life hidden within these long molecules, and technologists invent and improve methods of DNA analysis. The analysis of the nucleotide sequence of DNA occupies a special place among the methods developed. Thanks to the variety of sequencing technologies available, the process of decoding the sequence of genomic DNA (or whole genome sequencing) has become robust and inexpensive. Meanwhile the assembly of whole genome sequences remains a challenging task. In addition to the need to assemble millions of DNA fragments of different length (from 35 bp (Solexa) to 800 bp (Sanger)), great interest in analysis of microbial communities (metagenomes) of different complexities raises new problems and pushes some new requirements for sequence assembly tools to the forefront. The genome assembly process can be divided into two steps: draft assembly and assembly improvement (finishing). Despite the fact that automatically performed assembly (or draft assembly) is capable of covering up to 98% of the genome, in most cases, it still contains incorrectly assembled reads. The error rate of the consensus sequence produced at this stage is about 1/2000 bp. A finished genome represents the genome assembly of much higher accuracy (with no gaps or incorrectly assembled areas) and quality ({approx}1 error/10,000 bp), validated through a number of computer and laboratory experiments.

Human Contamination in Public Genome Assemblies.

Science.gov (United States)

Kryukov, Kirill; Imanishi, Tadashi

2016-01-01

Contamination in genome assembly can lead to wrong or confusing results when using such genome as reference in sequence comparison. Although bacterial contamination is well known, the problem of human-originated contamination received little attention. In this study we surveyed 45,735 available genome assemblies for evidence of human contamination. We used lineage specificity to distinguish between contamination and conservation. We found that 154 genome assemblies contain fragments that with high confidence originate as contamination from human DNA. Majority of contaminating human sequences were present in the reference human genome assembly for over a decade. We recommend that existing contaminated genomes should be revised to remove contaminated sequence, and that new assemblies should be thoroughly checked for presence of human DNA before submitting them to public databases.

Scoring-and-unfolding trimmed tree assembler: concepts, constructs and comparisons.

Science.gov (United States)

Narzisi, Giuseppe; Mishra, Bud

2011-01-15

Mired by its connection to a well-known -complete combinatorial optimization problem-namely, the Shortest Common Superstring Problem (SCSP)-historically, the whole-genome sequence assembly (WGSA) problem has been assumed to be amenable only to greedy and heuristic methods. By placing efficiency as their first priority, these methods opted to rely only on local searches, and are thus inherently approximate, ambiguous or error prone, especially, for genomes with complex structures. Furthermore, since choice of the best heuristics depended critically on the properties of (e.g. errors in) the input data and the available long range information, these approaches hindered designing an error free WGSA pipeline. We dispense with the idea of limiting the solutions to just the approximated ones, and instead favor an approach that could potentially lead to an exhaustive (exponential-time) search of all possible layouts. Its computational complexity thus must be tamed through a constrained search (Branch-and-Bound) and quick identification and pruning of implausible overlays. For his purpose, such a method necessarily relies on a set of score functions (oracles) that can combine different structural properties (e.g. transitivity, coverage, physical maps, etc.). We give a detailed description of this novel assembly framework, referred to as Scoring-and-Unfolding Trimmed Tree Assembler (SUTTA), and present experimental results on several bacterial genomes using next-generation sequencing technology data. We also report experimental evidence that the assembly quality strongly depends on the choice of the minimum overlap parameter k. SUTTA's binaries are freely available to non-profit institutions for research and educational purposes at http://www.bioinformatics.nyu.edu.

Fuel assembly and reactor core

International Nuclear Information System (INIS)

Aoyama, Motoo; Koyama, Jun-ichi; Uchikawa, Sadao; Bessho, Yasunori; Nakajima, Akiyoshi; Maruyama, Hiromi; Ozawa, Michihiro; Nakamura, Mitsuya.

1990-01-01

The present invention concerns fuel assemblies charged in a BWR type reactor and the reactor core. The fuel assembly comprises fuel rods containing burnable poisons and fuel rods not containing burnable poisons. Both of the highest and the lowest gadolinia concentrations of the fuel rods containing gadolinia as burnable poisons are present in the lower region of the fuel assembly. This can increase the spectral shift effect without increasing the maximum linear power density. (I.N.)

Cleaning device for fuel assemblies

International Nuclear Information System (INIS)

Kita, Kaoru.

1986-01-01

Purpose: To completely remove obstacles deposited to the lower sides of supporting lattices for fuel assemblies by utilizing water within a pit before reloading of the fuel assemblies. Constitution: A cylindrical can, to which a fuel assembly is inserted through the upper end opening thereof, is vertically disposed within water of a pit and the bottom of the can is communicated with a pump by way of a suction pipe and a filter device disposed out of the pit. While on the other hand, a fuel assembly is suspended downwardly by a crane and inserted to the inside of the can through the upper end of the opening thereof and supported therein followed by starting the pump. As a result, water in the pit is circulated through the inside of the can, suction pipe, filtering device, pump, discharge pipe and to the inside of the pit thereby enabling to completely eliminate obstacles deposited to the lower surface, etc. of supporting lattices for the fuel assembly supported within the can. (Takahashi, M.)

Inverse design of multicomponent assemblies

Science.gov (United States)

Piñeros, William D.; Lindquist, Beth A.; Jadrich, Ryan B.; Truskett, Thomas M.

2018-03-01

Inverse design can be a useful strategy for discovering interactions that drive particles to spontaneously self-assemble into a desired structure. Here, we extend an inverse design methodology—relative entropy optimization—to determine isotropic interactions that promote assembly of targeted multicomponent phases, and we apply this extension to design interactions for a variety of binary crystals ranging from compact triangular and square architectures to highly open structures with dodecagonal and octadecagonal motifs. We compare the resulting optimized (self- and cross) interactions for the binary assemblies to those obtained from optimization of analogous single-component systems. This comparison reveals that self-interactions act as a "primer" to position particles at approximately correct coordination shell distances, while cross interactions act as the "binder" that refines and locks the system into the desired configuration. For simpler binary targets, it is possible to successfully design self-assembling systems while restricting one of these interaction types to be a hard-core-like potential. However, optimization of both self- and cross interaction types appears necessary to design for assembly of more complex or open structures.

Compliant heterogeneous assemblies of micro-VCSELs as a new materials platform for integrated optoelectronics

Science.gov (United States)

Kang, Dongseok; Lee, Sung-Min; Kwong, Anthony; Yoon, Jongseung

2015-03-01

Despite many unique advantages, vertical cavity surface emitting lasers (VCSELs) have been available mostly on rigid, planar wafers over restricted areas, thereby limiting their usage for applications that can benefit from large-scale, programmable assemblies, hybrid integration with dissimilar materials and devices, or mechanically flexible constructions. Here, materials design and fabrication strategies that address these limitations of conventional VCSELs are presented. Specialized design of epitaxial materials and etching processes, together with printing-based deterministic assemblies and substrate thermal engineering, enabled defect-free release of microscale VCSELs and their device- and circuit-level implementation on non-native, flexible substrates with performance comparable to devices on the growth substrate.

Structural analysis of ITER sub-assembly tools

International Nuclear Information System (INIS)

Nam, K.O.; Park, H.K.; Kim, D.J.; Ahn, H.J.; Lee, J.H.; Kim, K.K.; Im, K.; Shaw, R.

2011-01-01

The ITER Tokamak assembly tools are purpose-built assembly tools to complete the ITER Tokamak machine which includes the cryostat and the components contained therein. The sector sub-assembly tools descried in this paper are main assembly tools to assemble vacuum vessel, thermal shield and toroidal filed coils into a complete 40 o sector. The 40 o sector sub-assembly tools are composed of sector sub-assembly tool, including radial beam, vacuum vessel supports and mid-plane brace tools. These tools shall have sufficient strength to transport and handle heavy weight of the ITER Tokamak machine reached several hundred tons. Therefore these tools should be designed and analyzed to confirm both the strength and structural stability even in the case of conservative assumptions. To verify structural stabilities of the sector sub-assembly tools in terms of strength and deflection, ANSYS code was used for linear static analysis. The results of the analysis show that these tools are designed with sufficient strength and stiffness. The conceptual designs of these tools are briefly described in this paper also.

Shock buffer for nuclear control assembly

International Nuclear Information System (INIS)

Bevilacqua, F.

1977-01-01

A shock buffer is provided for the gradual deceleration of a rapidly descending control element assembly in a nuclear reactor. The interactive buffer components are associated respectively with the movable control element assembly and part of the upper guide structure independent of and spaced from the fuel assemblies of the reactor

Electro-Optical Sensing Apparatus and Method for Characterizing Free-Space Electromagnetic Radiation

Science.gov (United States)

Zhang, Xi-Cheng; Libelo, Louis Francis; Wu, Qi

1999-09-14

Apparatus and methods for characterizing free-space electromagnetic energy, and in particular, apparatus/method suitable for real-time two-dimensional far-infrared imaging applications are presented. The sensing technique is based on a non-linear coupling between a low-frequency electric field and a laser beam in an electro-optic crystal. In addition to a practical counter-propagating sensing technique, a co-linear approach is described which provides longer radiated field--optical beam interaction length, thereby making imaging applications practical.

Bola-amphiphile self-assembly

DEFF Research Database (Denmark)

Svaneborg, Carsten

2012-01-01

Bola-amphiphiles are rod-like molecules where both ends of the molecule likes contact with water, while the central part of the molecule dislikes contact with water. What do such molecules do when they are dissolved in water? They self-assemble into micelles. This is a Dissipartive particle...... dynamics simulation of this self-assembly behaviour....

Assembling RNA Nanoparticles.

Science.gov (United States)

Xiao, Shou-Jun

2017-01-01

RNA nanoparticles are designed and self-assembled according to noncanonical interactions of naturally conserved RNA motifs and/or canonical Watson-Crick base-pairing interactions, which have potential applications in gene therapy and nanomedicine. These artificially engineered nanoparticles are mainly synthesized from in vitro transcribed RNAs, purified by denaturing and native polyacrylamide gel electrophoresis (PAGE), and characterized with native PAGE, AFM, and TEM technologies. The protocols of in vitro transcription, denaturing and native PAGE, and RNA nanoparticle self-assembly are described in detail.

A consensus approach to vertebrate de novo transcriptome assembly from RNA-seq data: Assembly of the duck (Anas platyrhynchos transcriptome.

Directory of Open Access Journals (Sweden)

Joanna eMoreton

2014-06-01

Full Text Available For vertebrate organisms where a reference genome is not available, de novo transcriptome assembly enables a cost effective insight into the identification of tissue specific or differentially expressed genes and variation of the coding part of the genome. However, since there are a number of different tools and parameters that can be used to reconstruct transcripts, it is difficult to determine an optimal method. Here we suggest a pipeline based on (1 assessing the performance of three different assembly tools (2 using both single and multiple k-mer approaches (3 examining the influence of the number of reads used in the assembly (4 merging assemblies from different tools. We use an example dataset from the vertebrate Anas platyrhynchos domestica (Pekin duck. We find that taking a subset of data enables a robust assembly to be produced by multiple methods without the need for very high memory capacity. The use of reads mapped back to transcripts (RMBT and CEGMA (Core Eukaryotic Genes Mapping Approach provides useful metrics to determine the completeness of assembly obtained. For this dataset the use of multiple k-mers in the assembly generated a more complete assembly as measured by greater number of RMBT and CEGMA score. Merged single k-mer assemblies are generally smaller but consist of longer transcripts, suggesting an assembly consisting of fewer fragmented transcripts. We suggest that the use of a subset of reads during assembly allows the relatively rapid investigation of assembly characteristics and can guide the user to the most appropriate transcriptome for particular downstream use. Transcriptomes generated by the compared assembly methods and the final merged assembly are freely available for download at http://dx.doi.org/10.6084/m9.figshare.1032613.

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

Science.gov (United States)

Hess, H; Ross, Jennifer L

2017-09-18

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

Design of the ITER tokamak assembly tools

Energy Technology Data Exchange (ETDEWEB)

Park, Hyunki [National Fusion Research Institute, 52 Eoeun-Dong, Yuseong-Gu, Daejon 305-333 (Korea, Republic of)], E-mail: hkpark@nfri.re.kr; Lee, Jaehyuk; Kim, Taehyung [SFA Engineering Corp., 42-7 Palyong-dong, Changwon-si, Gyeongsangnam-do 641-847 (Korea, Republic of); Song, Yunju [National Fusion Research Institute, 52 Eoeun-Dong, Yuseong-Gu, Daejon 305-333 (Korea, Republic of); Im, Kihak [ITER Organization, CEA Cadarasche, 13108 Saint Paul-lez-Durance (France); Kim, Byungchul; Lee, Hyeongon; Jung, Ki-Jung [National Fusion Research Institute, 52 Eoeun-Dong, Yuseong-Gu, Daejon 305-333 (Korea, Republic of)

2008-12-15

ITER tokamak assembly is mainly composed of lower cryostat activities, sector sub-assembly, sector assembly, in-vessel activities and ex-vessel activities. The main tools for sector sub-assembly procedures consists of upending tool, sector lifting tool, vacuum vessel support and bracing tool and sector sub-assembly tool. Conceptual design of assembly tools for sector sub-assembly procedures is described herein. The basic structure for upending tool has been developed under the assumption that upending is performed with crane which will be installed in Tokamak building. Sector lifting tool is designed to adjust the position of a sector to minimize the difference between the center of the tokamak building crane and the center of gravity of the sector. Sector sub-assembly tool is composed of special frame for the fine adjustment of position control with 6 degrees of freedom. The design of VV support and bracing tool for four kinds of VV 40 deg. sectors has been developed. Also, structural analysis for upending tool, sector sub-assembly tool has been studied using ANSYS for the situation of an applied load with the same dead weight multiplied by 3/4. The results of structural analyses for these tools were below the allowable values.

Fuel assembly for a nuclear reactor

International Nuclear Information System (INIS)

Gjertsen, R.K.

1982-01-01

A fuel assembly in a nuclear reactor comprises a locking mechanism that is capable of locking the fuel assembly to the core plate of a nuclear reactor to prevent inadvertent movement of the fuel assembly. The locking mechanism comprises a ratchet mechanism 108 that allows the fuel assembly to be easily locked to the core plate but prevents unlocking except when the ratchet is disengaged. The ratchet mechanism is coupled to the locking mechanism by a rotatable guide tube for a control rod or water displacer rod. (author)

Design configuration of GCFR core assemblies

International Nuclear Information System (INIS)

LaBar, M.P.; Lee, G.E.; Meyer, R.J.

1980-05-01

The current design configurations of the core assemblies for the gas-cooled fast reactor (GCFR) demonstration plant reactor core conceptual design are described. Primary emphasis is placed upon the design innovations that have been incorporated in the design of the core assemblies since the establishment of the initial design of an upflow GCFR core. A major feature of the design configurations is that they are prototypical of core assemblies for use in commercial plants; a larger number of the same assemblies would be used in a commercial plant

Primary assembly of soil communities: disentangling the effect of dispersal and local environment.

Science.gov (United States)

Ingimarsdóttir, María; Caruso, Tancredi; Ripa, Jörgen; Magnúsdóttir, Olöf Birna; Migliorini, Massimo; Hedlund, Katarina

2012-11-01

It has long been recognised that dispersal abilities and environmental factors are important in shaping invertebrate communities, but their relative importance for primary soil community assembly has not yet been disentangled. By studying soil communities along chronosequences on four recently emerged nunataks (ice-free land in glacial areas) in Iceland, we replicated environmental conditions spatially at various geographical distances. This allowed us to determine the underlying factors of primary community assembly with the help of metacommunity theories that predict different levels of dispersal constraints and effects of the local environment. Comparing community assembly of the nunataks with that of non-isolated deglaciated areas indicated that isolation of a few kilometres did not affect the colonisation of the soil invertebrates. When accounting for effects of geographical distances, soil age and plant richness explained a significant part of the variance observed in the distribution of the oribatid mites and collembola communities, respectively. Furthermore, null model analyses revealed less co-occurrence than expected by chance and also convergence in the body size ratio of co-occurring oribatids, which is consistent with species sorting. Geographical distances influenced species composition, indicating that the community is also assembled by dispersal, e.g. mass effect. When all the results are linked together, they demonstrate that local environmental factors are important in structuring the soil community assembly, but are accompanied with effects of dispersal that may "override" the visible effect of the local environment.

Deterministic nanoparticle assemblies: from substrate to solution

International Nuclear Information System (INIS)

Barcelo, Steven J; Gibson, Gary A; Yamakawa, Mineo; Li, Zhiyong; Kim, Ansoon; Norris, Kate J

2014-01-01

The deterministic assembly of metallic nanoparticles is an exciting field with many potential benefits. Many promising techniques have been developed, but challenges remain, particularly for the assembly of larger nanoparticles which often have more interesting plasmonic properties. Here we present a scalable process combining the strengths of top down and bottom up fabrication to generate deterministic 2D assemblies of metallic nanoparticles and demonstrate their stable transfer to solution. Scanning electron and high-resolution transmission electron microscopy studies of these assemblies suggested the formation of nanobridges between touching nanoparticles that hold them together so as to maintain the integrity of the assembly throughout the transfer process. The application of these nanoparticle assemblies as solution-based surface-enhanced Raman scattering (SERS) materials is demonstrated by trapping analyte molecules in the nanoparticle gaps during assembly, yielding uniformly high enhancement factors at all stages of the fabrication process. (paper)

SAGE: String-overlap Assembly of GEnomes.

Science.gov (United States)

Ilie, Lucian; Haider, Bahlul; Molnar, Michael; Solis-Oba, Roberto

2014-09-15

De novo genome assembly of next-generation sequencing data is one of the most important current problems in bioinformatics, essential in many biological applications. In spite of significant amount of work in this area, better solutions are still very much needed. We present a new program, SAGE, for de novo genome assembly. As opposed to most assemblers, which are de Bruijn graph based, SAGE uses the string-overlap graph. SAGE builds upon great existing work on string-overlap graph and maximum likelihood assembly, bringing an important number of new ideas, such as the efficient computation of the transitive reduction of the string overlap graph, the use of (generalized) edge multiplicity statistics for more accurate estimation of read copy counts, and the improved use of mate pairs and min-cost flow for supporting edge merging. The assemblies produced by SAGE for several short and medium-size genomes compared favourably with those of existing leading assemblers. SAGE benefits from innovations in almost every aspect of the assembly process: error correction of input reads, string-overlap graph construction, read copy counts estimation, overlap graph analysis and reduction, contig extraction, and scaffolding. We hope that these new ideas will help advance the current state-of-the-art in an essential area of research in genomics.

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

Force and time-dependent self-assembly, disruption and recovery of supramolecular peptide amphiphile nanofibers.

Science.gov (United States)

Dikecoglu, F Begum; Topal, Ahmet E; Ozkan, Alper D; Tekin, E Deniz; Tekinay, Ayse B; Guler, Mustafa O; Dana, Aykutlu

2018-07-13

Biological feedback mechanisms exert precise control over the initiation and termination of molecular self-assembly in response to environmental stimuli, while minimizing the formation and propagation of defects through self-repair processes. Peptide amphiphile (PA) molecules can self-assemble at physiological conditions to form supramolecular nanostructures that structurally and functionally resemble the nanofibrous proteins of the extracellular matrix, and their ability to reconfigure themselves in response to external stimuli is crucial for the design of intelligent biomaterials systems. Here, we investigated real-time self-assembly, deformation, and recovery of PA nanofibers in aqueous solution by using a force-stabilizing double-pass scanning atomic force microscopy imaging method to disrupt the self-assembled peptide nanofibers in a force-dependent manner. We demonstrate that nanofiber damage occurs at tip-sample interaction forces exceeding 1 nN, and the damaged fibers subsequently recover when the tip pressure is reduced. Nanofiber ends occasionally fail to reconnect following breakage and continue to grow as two individual nanofibers. Energy minimization calculations of nanofibers with increasing cross-sectional ellipticity (corresponding to varying levels of tip-induced fiber deformation) support our observations, with high-ellipticity nanofibers exhibiting lower stability compared to their non-deformed counterparts. Consequently, tip-mediated mechanical forces can provide an effective means of altering nanofiber integrity and visualizing the self-recovery of PA assemblies.

Self-Assembly of Block and Graft Copolymers in Organic Solvents: An Overview of Recent Advances

Directory of Open Access Journals (Sweden)

Leonard Ionut Atanase

2018-01-01

Full Text Available This review is an attempt to update the recent advances in the self-assembly of amphiphilic block and graft copolymers. Their micellization behavior is highlighted for linear AB, ABC triblock terpolymers, and graft structures in non-aqueous selective polar and non-polar solvents, including solvent mixtures and ionic liquids. The micellar characteristics, such as particle size, aggregation number, and morphology, are examined as a function of the copolymers’ architecture and molecular characteristics.

Research on Outfitting Virtual Assembly based on Ergonomics

Directory of Open Access Journals (Sweden)

Jiang Zuhua

2018-01-01

Full Text Available To improve the present situation where the assembly work of ship outfitting depends on manual experiential operation, the thesis, taking outfitting assembly operation as the research object and optimal assembly path as the target, puts forward the simulation method and procedure of outfitting virtual assembly considering operational posture, operational load, reachability and visibility and other ergonomic factors, taking pipe assembly operation of ship section as the application example. The results show that the method can obtain better assembly operation path, avoid interference of workers’ operation process and improve the efficiency of assembly operation.

Ordinary General Assembly

CERN Multimedia

Association du personnel

2010-01-01

Tuesday 20 April at 10.00 Council Chamber, Bldg 503 In conformity with the Statutes of the Staff Association, an ordinary General Assembly is organized once a year (article IV.2.1). Agenda Adoption of the Agenda Approval of the Draft Minutes of the Ordinary General Assembly of 12 May 2009 Presentation and approval of the Activity Report 2009 Presentation and approval of the Financial Report 2009 Presentation and approval of the Auditors Report 2009 Programme for 2010 Presentation et and approval of the draft budget and subscription rate 2010 Modifications to the statutes of the association Election of the Election Committee Election of the Board of Auditors Miscellaneous We remind members of article IV.3.4 in the Statutes of the Association which reads: “After having dealt with all the items on the agenda, the members may, with the consent of the Assembly, have other matters discussed, but decisions may be taken only on the items listed on the agenda...

Fuel assembly

International Nuclear Information System (INIS)

Ueda, Sei; Ando, Ryohei; Mitsutake, Toru.

1995-01-01

The present invention concerns a fuel assembly suitable to a BWR-type reactor and improved especially with the nuclear characteristic, heat performance, hydraulic performance, dismantling or assembling performance and economical property. A part of poison rods are formed as a large-diameter/multi-region poison rods having a larger diameter than a fuel rod. A large number of fuel rods are disposed surrounding a large diameter water rod and a group of the large-diameter/multi-region poison rods in adjacent with the water rod. The large-diameter water rod has a burnable poison at the tube wall portion. At least a portion of the large-diameter poison rods has a coolant circulation portion allowing coolants to circulate therethrough. Since the large-diameter poison rods are disposed at a position of high neutron fluxes, a large neutron multiplication factor suppression effect can be provided, thereby enabling to reduce the number of burnable poison rods relative to fuels. As a result, power peaking in the fuel assembly is moderated and a greater amount of plutonium can be loaded. In addition the flow of cooling water which tends to gather around the large diameter water rod can be controlled to improve cooling performance of fuels. (N.H.)

Self-Assembly of Large-Scale Shape-Controlled DNA Nano-Structures

Science.gov (United States)

2014-12-16

for single-molecule imaging. Nano Lett. 11, 657-660 (2011). 46. Dang, X. N. et at. Virus -templated self-assembled single-walled carbon nanotubes for...email: alik(a)rics.bwh.harvard edu). NATURE C0,M.MUN! CAT !0N5 14:2275 I DOI: 10.1038/ncomm53275 | wwwnature.com/naturecommunications 1 @ 2013 Macmillan...prevent non-specific binding between hydrogel and microtube, the inside surface of microtube was treated with a corona treater (BD-20AC from Electro

Self-assembled biomimetic nanoreactors I: Polymeric template

Science.gov (United States)

McTaggart, Matt; Malardier-Jugroot, Cecile; Jugroot, Manish

2015-09-01

The variety of nanoarchitectures made feasible by the self-assembly of alternating copolymers opens new avenues for biomimicry. Indeed, self-assembled structures allow the development of nanoreactors which combine the efficiency of high surface area metal active centres to the effect of confinement due to the very small cavities generated by the self-assembly process. A novel self-assembly of high molecular weight alternating copolymers is characterized in the present study. The self-assembly is shown to organize into nanosheets, providing a 2 nm hydrophobic cavity with a 1D confinement.

Self-Controlling Rig for Jaw Crusher Assembly

OpenAIRE

Saurabh Jadhav; Anup Pawar

2017-01-01

The aim of the work is to develop a method for easy assembly of the bearing in the housing by standardized way. The assembly of bearing should take place on the atomized set up. Based on this method a assembly setup was constructed which enables to assembly of the shaft with bearing of different models of jaw crusher. First tests were done with manual alignment and it shows that with proper alignment shaft assembly is very easy operation and also safe. Results of those tests show that the dev...

Parallel assembling and equation solving via graph algorithms with an application to the FE simulation of metal extrusion processes

CERN Document Server

Unterkircher, A

2005-01-01

We propose methods for parallel assembling and iterative equation solving based on graph algorithms. The assembling technique is independent of dimension, element type and model shape. As a parallel solving technique we construct a multiplicative symmetric Schwarz preconditioner for the conjugate gradient method. Both methods have been incorporated into a non-linear FE code to simulate 3D metal extrusion processes. We illustrate the efficiency of these methods on shared memory computers by realistic examples.

A simple and versatile system for the ATP-dependent assembly of chromatin.

Science.gov (United States)

Khuong, Mai T; Fei, Jia; Cruz-Becerra, Grisel; Kadonaga, James T

2017-11-24

Chromatin is the natural form of DNA in the eukaryotic nucleus and is the substrate for diverse biological phenomena. The functional analysis of these processes ideally would be carried out with nucleosomal templates that are assembled with customized core histones, DNA sequences, and chromosomal proteins. Here we report a simple, reliable, and versatile method for the ATP-dependent assembly of evenly spaced nucleosome arrays. This minimal chromatin assembly system comprises the Drosophila nucleoplasmin-like protein (dNLP) histone chaperone, the imitation switch (ISWI) ATP-driven motor protein, core histones, template DNA, and ATP. The dNLP and ISWI components were synthesized in bacteria, and each protein could be purified in a single step by affinity chromatography. We show that the dNLP-ISWI system can be used with different DNA sequences, linear or circular DNA, bulk genomic DNA, recombinant or native Drosophila core histones, native human histones, the linker histone H1, the non-histone chromosomal protein HMGN2, and the core histone variants H3.3 and H2A.V. The dNLP-ISWI system should be accessible to a wide range of researchers and enable the assembly of customized chromatin with specifically desired DNA sequences, core histones, and other chromosomal proteins. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Gigadalton-scale shape-programmable DNA assemblies

Science.gov (United States)

Wagenbauer, Klaus F.; Sigl, Christian; Dietz, Hendrik

2017-12-01

Natural biomolecular assemblies such as molecular motors, enzymes, viruses and subcellular structures often form by self-limiting hierarchical oligomerization of multiple subunits. Large structures can also assemble efficiently from a few components by combining hierarchical assembly and symmetry, a strategy exemplified by viral capsids. De novo protein design and RNA and DNA nanotechnology aim to mimic these capabilities, but the bottom-up construction of artificial structures with the dimensions and complexity of viruses and other subcellular components remains challenging. Here we show that natural assembly principles can be combined with the methods of DNA origami to produce gigadalton-scale structures with controlled sizes. DNA sequence information is used to encode the shapes of individual DNA origami building blocks, and the geometry and details of the interactions between these building blocks then control their copy numbers, positions and orientations within higher-order assemblies. We illustrate this strategy by creating planar rings of up to 350 nanometres in diameter and with atomic masses of up to 330 megadaltons, micrometre-long, thick tubes commensurate in size to some bacilli, and three-dimensional polyhedral assemblies with sizes of up to 1.2 gigadaltons and 450 nanometres in diameter. We achieve efficient assembly, with yields of up to 90 per cent, by using building blocks with validated structure and sufficient rigidity, and an accurate design with interaction motifs that ensure that hierarchical assembly is self-limiting and able to proceed in equilibrium to allow for error correction. We expect that our method, which enables the self-assembly of structures with sizes approaching that of viruses and cellular organelles, can readily be used to create a range of other complex structures with well defined sizes, by exploiting the modularity and high degree of addressability of the DNA origami building blocks used.

Three-dimensional assemblies of graphene prepared by a novel chemical reduction-induced self-assembly method

KAUST Repository

Zhang, Lianbin

2012-01-01

In this study, three-dimensional (3D) graphene assemblies are prepared from graphene oxide (GO) by a facile in situ reduction-assembly method, using a novel, low-cost, and environment-friendly reducing medium which is a combination of oxalic acid (OA) and sodium iodide (NaI). It is demonstrated that the combination of a reducing acid, OA, and NaI is indispensable for effective reduction of GO in the current study and this unique combination (1) allows for tunable control over the volume of the thus-prepared graphene assemblies and (2) enables 3D graphene assemblies to be prepared from the GO suspension with a wide range of concentrations (0.1 to 4.5 mg mL-1). To the best of our knowledge, the GO concentration of 0.1 mg mL-1 is the lowest GO concentration ever reported for preparation of 3D graphene assemblies. The thus-prepared 3D graphene assemblies exhibit low density, highly porous structures, and electrically conducting properties. As a proof of concept, we show that by infiltrating a responsive polymer of polydimethylsiloxane (PDMS) into the as-resulted 3D conducting network of graphene, a conducting composite is obtained, which can be used as a sensing device for differentiating organic solvents with different polarity. © 2012 The Royal Society of Chemistry.

Spontaneous Assembly of Exopolymers from Phytoplankton

Directory of Open Access Journals (Sweden)

Yong-Xue Ding

2009-01-01

Full Text Available Phytoplankton exopolymeric substances (EPS contribute significantly to the dissolved organic car bon (DOC pool in the ocean, playing crucial roles in the surface ocean car bon cycle. Recent studies have demonstrated that ~10% of marine DOC can self-assemble as microgels through electro static Ca bonds providing hotspots of enriched microbial substrate. How ever, the question whether EPS can self-assemble and the formation mechanisms for EPS microgels have not been examined. Here were port that EPS from three representative phytoplankton species, Synechococcus, Emiliania huxleyi, and Skeletonema costatum can spontaneously self assemble in artificial sea water (ASW, forming microscopic gels of ~ 3 - 4 __m in diameter. Different from the marine DOC polymers assembly, these EPS samples can self-assemble in Ca2+-free ASW. Further experiments from fluorescence enhancement and chemical composition analysis confirmed the existence of fair amounts of hydrophobic domains in these EPS samples. These results suggest that hydrophobic interactions play a key role in the assembly of EPS from these three species of marine phytoplankton.

Self-assembly of pi-conjugated peptides in aqueous environments leading to energy-transporting bioelectronic nanostructures

Energy Technology Data Exchange (ETDEWEB)

Tavor, John [Johns Hopkins Univ., Baltimore, MD (United States)

2016-12-06

The realization of new supramolecular pi-conjugated organic structures inspired and driven by peptide-based self-assembly will offer a new approach to interface with the biotic environment in a way that will help to meet many DOE-recognized grand challenges. Previously, we developed pi-conjugated peptides that undergo supramolecular self-assembly into one-dimensional (1-D) organic electronic nanomaterials under benign aqueous conditions. The intermolecular interactions among the pi-conjugated organic segments within these nanomaterials lead to defined perturbations of their optoelectronic properties and yield nanoscale conduits that support energy transport within individual nanostructures and throughout bulk macroscopic collections of nanomaterials. Our objectives for future research are to construct and study biomimetic electronic materials for energy-related technology optimized for harsher non-biological environments where peptide-driven self-assembly enhances pi-stacking within nanostructured biomaterials, as detailed in the following specific tasks: (1) synthesis and detailed optoelectronic characterization of new pi-electron units to embed within homogeneous self assembling peptides, (2) molecular and data-driven modeling of the nanomaterial aggregates and their higher-order assemblies, and (3) development of new hierarchical assembly paradigms to organize multiple electronic subunits within the nanomaterials leading to heterogeneous electronic properties (i.e. gradients and localized electric fields). These intertwined research tasks will lead to the continued development and fundamental mechanistic understanding of a powerful bioinspired materials set capable of making connections between nanoscale electronic materials and macroscopic bulk interfaces, be they those of a cell, a protein or a device.

Subcritical assemblies, use and their feasibility assessment

International Nuclear Information System (INIS)

Haroon, M.R.

1982-03-01

In developing countries, subcritical assemblies can be a useful tool for training and research in the field of nuclear technology with minimum cost. The historical development of subcritical assemblies and the reactor physics experiments which can be carried out using this facility are outlined. The different types of subcritical assemblies have been described and material requirements for each assembly have been pointed out. (author)

Virtual Reality and Haptics for Product Assembly

Directory of Open Access Journals (Sweden)

Maria Teresa Restivo

2012-01-01

Full Text Available Haptics can significantly enhance the user's sense of immersion and interactivity. An industrial application of virtual reality and haptics for product assembly is described in this paper, which provides a new and low-cost approach for product assembly design, assembly task planning and assembly operation training. A demonstration of the system with haptics device interaction was available at the session of exp.at'11.

Electrode assembly for a lithium ion battery, process for the production of such electrode assembly, and lithium ion battery comprising such electrode assemblies

NARCIS (Netherlands)

Mulder, F.M.; Wagemaker, M.

2013-01-01

The invention provides an electrode assembly for a lithium ion battery, the electrode assembly comprising a lithium storage electrode layer on a current collector, wherein the lithium storage electrode layer is a porous layer having a porosity in the range of -35 %, with pores having pore widths in

Effect of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism

Energy Technology Data Exchange (ETDEWEB)

Liu, Xianbin, E-mail: xbliu@imr.ac.cn; Shan, Dayong; Song, Yingwei; Han, En-hou

2015-01-15

The influence of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism have been investigated by electrochemical measurements, scanning electron microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) analysis. The self-assembled experiment on the AM60B magnesium alloy indicates that the corrosion susceptibility decreases with increasing assembled time until 24 h on cast AM60B alloy and then increases with increase of the assembled time proved by EIS measurement and potentiodynamic curves. The self-assembled experiments on pure magnesium and various heat treated cast AM60B magnesium alloy illuminate that the dissolved aluminum in magnesium solid solution is the key factor for assembled efficiency and is hard to self-assemble on the pure magnesium without aluminum. The corrosion resistance of self-assembled film on AM60B magnesium alloy is monotonically increasing with the dissolved aluminum. The results of XPS analysis reveal the assembled mechanism on AM60B and corroborate the function of Al element. - Highlights: • It is hard to self-assemble on the pure magnesium. • 24 h assembled film has the low corrosion susceptibility by EIS and polarization. • The corrosion susceptibility of SAMs film lie on the Al atom state in AM60B. • The corrosion susceptibility of SAMs film is decreasing with the dissolved Al.

Effect of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism

International Nuclear Information System (INIS)

Liu, Xianbin; Shan, Dayong; Song, Yingwei; Han, En-hou

2015-01-01

The influence of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism have been investigated by electrochemical measurements, scanning electron microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) analysis. The self-assembled experiment on the AM60B magnesium alloy indicates that the corrosion susceptibility decreases with increasing assembled time until 24 h on cast AM60B alloy and then increases with increase of the assembled time proved by EIS measurement and potentiodynamic curves. The self-assembled experiments on pure magnesium and various heat treated cast AM60B magnesium alloy illuminate that the dissolved aluminum in magnesium solid solution is the key factor for assembled efficiency and is hard to self-assemble on the pure magnesium without aluminum. The corrosion resistance of self-assembled film on AM60B magnesium alloy is monotonically increasing with the dissolved aluminum. The results of XPS analysis reveal the assembled mechanism on AM60B and corroborate the function of Al element. - Highlights: • It is hard to self-assemble on the pure magnesium. • 24 h assembled film has the low corrosion susceptibility by EIS and polarization. • The corrosion susceptibility of SAMs film lie on the Al atom state in AM60B. • The corrosion susceptibility of SAMs film is decreasing with the dissolved Al

Development of an advanced 16x165 Westinghouse type PWR fuel assembly for Slovenia

International Nuclear Information System (INIS)

Boone, M. L.; King, S. J.; Pulver, E. F.; Jeon, K.-L.; Esteves, R.; Kurincic, B.

2004-01-01

Industrias Nucleares do Brasil (INB), KEPCO Nuclear Fuel Company, Ltd. (KNFC), and Westinghouse Electric Company (Westinghouse) have jointly designed an advanced 16x16 Westinghouse type PWR fuel assembly. This advanced 16x16 Westinghouse type PWR fuel assembly, which will be implemented in both Kori Unit 2 (in Korea) and Angra Unit 1 (in Brazil) in January and March 2005, respectively, is an integral part of the utilities fuel management strategy. This same fuel design has also been developed for future use in Krsko Unit 1 (in Slovenia). In this paper we will describe the front-end nuclear fuel management activities utilized by the joint development team and describe how these activities played an integral part in defining the direction of the advanced 16x16 Westinghouse type PWR fuel assembly design. Additionally, this paper will describe how this design demonstrates improved margins under high duty plant operating conditions. The major reason for initiating this joint development program was to update the current 16x16 fuel assembly, which is also called 16STD. The current 16STD fuel assembly contains a non-optimized fuel rod diameter for the fuel rod pitch (i.e. 9.5 mm OD fuel rods at a 0.485 inch pitch), non-neutronic efficient components (i.e. Inconel Mid grids), no Intermediate Flow Mixer (IFM) grids, and other mechanical features. The advanced 16x16 fuel assembly is being designed for peak rod average burnups of up to 75 MWd/kgU and will use an optimized fuel rod diameter (i.e. 9.14 mm OD ZIRLO TM fuel rods), neutronic efficient components (i.e. ZIRLO TM Mid grids), ZIRLO TM Intermediate Flow Mixer (IFM) grids to improve Departure from Nucleate Boiling (DNB) margin, and many other mechanical features that improve design margins. Nuclear design activities in the areas of fuel cycle cost and fuel management were performed in parallel to the fuel assembly design efforts. As the change in reactivity due to the change in the fuel rod diameter influences directly

TracWorks - global fuel assembly data management

International Nuclear Information System (INIS)

Cooney, B.F.

1997-01-01

The TracWorks Data Management System is a workstation-based software product that provides a utility with a single, broadly available, regularly updated source for virtually every data item available for a fuel assembly or core component. TracWorks is designed to collect, maintain and provide information about assembly and component locations and movements during the refuelling process and operation, assembly burnup and isotopic inventory (both in-core and out-of-core), pin burnup and isotopics for pins that have been removed from their original assemblies, assembly and component inspection results (including video) and manufacturing data provided by the fabrication plant. (UK)