Journal articles: 'Pivots assembly'

1

Pflueger, Nathan. "Graph reductions, binary rank, and pivots in gene assembly." Discrete Applied Mathematics 159, no. 17 (October 2011): 2117–34. http://dx.doi.org/10.1016/j.dam.2011.07.007.

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Brijder, Robert, and Hendrik Jan Hoogeboom. "Maximal pivots on graphs with an application to gene assembly." Discrete Applied Mathematics 158, no. 18 (November 2010): 1977–85. http://dx.doi.org/10.1016/j.dam.2010.08.030.

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Lim, Jonas J. B., and Arthur G. Erdman. "Application of Type Synthesis Theory to the Redesign of a Complex Surgical Instrument." Journal of Biomechanical Engineering 124, no. 3 (May 21, 2002): 265–72. http://dx.doi.org/10.1115/1.1468635.

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Surgical instruments consist of basic mechanical components such as gears, links, pivots, sliders, etc., which are common in mechanical design. This paper describes the application of a method in the analysis and design of complex surgical instruments such as those employed in laparoscopic surgery. This is believed to be the first application of type synthesis theory to a complex medical instrument. Type synthesis is a methodology that can be applied during the conceptual phase of mechanical design. A handle assembly from a patented laparoscopic surgical stapler is used to illustrate the application of the design method developed. Type synthesis is applied on specific subsystems of the mechanism within the handle assembly where alternative design concepts are generated. Chosen concepts are then combined to form a new conceptual design for the handle assembly. The new handle assembly is improved because it has fewer number of parts, is a simpler design and is easier to assemble. Surgical instrument designers may use the methodology presented here to analyze the mechanical subsystems within complex instruments and to create new options that may offer improvements to the original design.

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Pigoski, T. M., and J. Duffy. "An Inverse Force Analysis of a Planar Two-Spring System." Journal of Mechanical Design 117, no. 4 (December 1, 1995): 548–53. http://dx.doi.org/10.1115/1.2826717.

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A closed-form inverse force analysis was performed on a planar two-spring system. The two springs were grounded to pivots at one end and attached to a common pivot at the other. A known force was applied to the common pivot of the system, and it was required to determine all of the assembly configurations. By variable elimination, a sixth degree polynomial in the resultant length of one spring was derived, and from this, six real solutions of the point of application of force were obtained. Following this, the applied force was incremented along a line and the six paths of the moving pivot were tracked starting from the zero-load configurations. An analysis of these results showed stability phenomena indicating the workspace of this system contained regions of negative spring stiffness and points of catastrophe.

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Kiener, Lionel, Hervé Saudan, Florent Cosandier, Gérald Perruchoud, and Peter Spanoudakis. "Innovative concept of compliant mechanisms made by additive manufacturing." MATEC Web of Conferences 304 (2019): 07002. http://dx.doi.org/10.1051/matecconf/201930407002.

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The complete redesign for Additive Manufacturing of compliant mechanism structures enables CSEM to develop innovative concepts to drastically reduce the need of machining and assembly after additive manufacturing. Support structures under flexure blades are thus minimised and the overall process becomes more streamlined. Moreover, this concept allows us to easily design and produce monolithic cross flexure pivots with interlocked flexible blades. Based on this concept, CSEM is now developing new architectures of Compliant Mechanisms based on Additive Manufacturing (COMAM) for the European Space Agency (ESA) in the frame of a GSTP research project. The past and current work of design, 3D printing and testing on several compliant mechanisms are presented. These demonstrators will be used as use-case for future high-precision and harsh environment applications such as cryogenic and space.

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Robinson, Graham C., Markus Kaufmann, Céline Roux, Jacobo Martinez-Font, Michael Hothorn, Stéphane Thore, and Teresa B. Fitzpatrick. "Crystal structure of the pseudoenzyme PDX1.2 in complex with its cognate enzyme PDX1.3: a total eclipse." Acta Crystallographica Section D Structural Biology 75, no. 4 (April 1, 2019): 400–415. http://dx.doi.org/10.1107/s2059798319002912.

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Pseudoenzymes have burst into the limelight recently as they provide another dimension to regulation of cellular protein activity. In the eudicot plant lineage, the pseudoenzyme PDX1.2 and its cognate enzyme PDX1.3 interact to regulate vitamin B6 biosynthesis. This partnership is important for plant fitness during environmental stress, in particular heat stress. PDX1.2 increases the catalytic activity of PDX1.3, with an overall increase in vitamin B6 biosynthesis. However, the mechanism by which this is achieved is not known. In this study, the Arabidopsis thaliana PDX1.2–PDX1.3 complex was crystallized in the absence and presence of ligands, and attempts were made to solve the X-ray structures. Three PDX1.2–PDX1.3 complex structures are presented: the PDX1.2–PDX1.3 complex as isolated, PDX1.2–PDX1.3-intermediate (in the presence of substrates) and a catalytically inactive complex, PDX1.2–PDX1.3-K97A. Data were also collected from a crystal of a selenomethionine-substituted complex, PDX1.2–PDX1.3-SeMet. In all cases the protein complexes assemble as dodecamers, similar to the recently reported individual PDX1.3 homomer. Intriguingly, the crystals of the protein complex are statistically disordered owing to the high degree of structural similarity of the individual PDX1 proteins, such that the resulting configuration is a composite of both proteins. Despite the differential methionine content, selenomethionine substitution of the PDX1.2–PDX1.3 complex did not resolve the problem. Furthermore, a comparison of the catalytically competent complex with a noncatalytic complex did not facilitate the resolution of the individual proteins. Interestingly, another catalytic lysine in PDX1.3 (Lys165) that pivots between the two active sites in PDX1 (P1 and P2), and the corresponding glutamine (Gln169) in PDX1.2, point towards P1, which is distinctive to the initial priming for catalytic action. This state was previously only observed upon trapping PDX1.3 in a catalytically operational state, as Lys165 points towards P2 in the resting state. Overall, the study shows that the integration of PDX1.2 into a heteromeric dodecamer assembly with PDX1.3 does not cause a major structural deviation from the overall architecture of the homomeric complex. Nonetheless, the structure of the PDX1.2–PDX1.3 complex highlights enhanced flexibility in key catalytic regions for the initial steps of vitamin B6 biosynthesis. This report highlights what may be an intrinsic limitation of X-ray crystallography in the structural investigation of pseudoenzymes.

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Krajewski, Casimir, Randolph I. Melville, and William W. Porter. "Pivot bushing assembly application." Journal of the Acoustical Society of America 86, no. 1 (July 1989): 452. http://dx.doi.org/10.1121/1.398247.

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Garner, Brian A., Jaeho Shim, and Scott Wilson. "An Apparatus and Protocol to Measure Shoulder Girdle Strength." Journal of Medical Devices 1, no. 4 (August 10, 2007): 246–53. http://dx.doi.org/10.1115/1.2796190.

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Muscles actuating the shoulder girdle are important for stabilizing the scapula and coordinating phased kinematics of the shoulder complex. If these muscles become weak or imbalanced, joint instability and injury may result. Reliable measurement of shoulder strength is thus important for prevention, diagnosis, and rehabilitation of shoulder problems. To date, studies quantifying the strength of the shoulder girdle are limited. The purpose of this work was to design and evaluate a custom apparatus and corresponding protocol for measuring maximal, voluntary, isometric strength of the shoulder girdle during various forms of shrugging exercise. A custom apparatus was constructed as a rigid frame with a vertical post supporting a seat, seat back, and horizontal beam. The beam extends laterally on either side beyond and around the shoulders of a seated subject. A pair of arm extension members pivots on the beam about an axis aligned with the shoulder flexion-extension axis. These members can be locked in place at any angle. Between them is mounted a force-sensing grip assembly, which can be adjusted proximally or distally to accommodate varying shoulder girdle positions. Subjects grasp the grip assembly handles with extended elbows and push or pull as forcefully as possible. Nine female and ten male subjects participated in a protocol using the apparatus to measure maximum isometric force generated at three positions each for elevation, depression, protraction, and retraction of the shoulder girdle (3positions×4modes=12tests). A video motion capture system was used to measure shoulder girdle angles. The reliability of the approach was evaluated based on the repeatability of measured shoulder elevation angle, protraction angle, and total force over three days of testing. The apparatus performed well during the tests, providing a stable, rigid, yet adjustable platform for measuring shoulder girdle strength. Repeatability of force measurements was interpreted as very good to excellent, with intraclass correlation coefficient (ICC) (2,1) values ranging from 0.83 to 0.95 for all tests except one (ICC=0.79). Repeatability of angle measurements was interpreted as good to excellent. For tests measuring elevation and depression strength, the ICC of elevation angle ranged from 0.85 to 0.89. For tests measuring protraction and retraction strength, the ICC of protraction angle ranged from 0.68 to 0.88. This type of apparatus could be an effective clinical tool for measuring strength in the shoulder girdle muscles. Use of the video motion capture system is optional.

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Hahn, Hyunggu, Sang Ho Park, Hyun-Jung Kim, Sunghoon Kim, and Byung Woo Han. "The DRS–AIMP2–EPRS subcomplex acts as a pivot in the multi-tRNA synthetase complex." IUCrJ 6, no. 5 (August 24, 2019): 958–67. http://dx.doi.org/10.1107/s2052252519010790.

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Aminoacyl-tRNA synthetases (ARSs) play essential roles in protein biosynthesis as well as in other cellular processes, often using evolutionarily acquired domains. For possible cooperativity and synergistic effects, nine ARSs assemble into the multi-tRNA synthetase complex (MSC) with three scaffold proteins: aminoacyl-tRNA synthetase complex-interacting multifunctional proteins 1, 2 and 3 (AIMP1, AIMP2 and AIMP3). X-ray crystallographic methods were implemented in order to determine the structure of a ternary subcomplex of the MSC comprising aspartyl-tRNA synthetase (DRS) and two glutathione S-transferase (GST) domains from AIMP2 and glutamyl-prolyl-tRNA synthetase (AIMP2GST and EPRSGST, respectively). While AIMP2GST and EPRSGST interact via conventional GST heterodimerization, DRS strongly interacts with AIMP2GST via hydrogen bonds between the α7–β9 loop of DRS and the β2–α2 loop of AIMP2GST, where Ser156 of AIMP2GST is essential for the assembly. Structural analyses of DRS–AIMP2GST–EPRSGST reveal its pivotal architecture in the MSC and provide valuable insights into the overall assembly and conditionally required disassembly of the MSC.

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Choodoung, Sakkarin, and Uttapol Smutkupt. "Analysis Design for Assembly by MTM-2 (Methods Time Measurement-2) for Wood Joints in Furniture." Advanced Materials Research 566 (September 2012): 394–98. http://dx.doi.org/10.4028/www.scientific.net/amr.566.394.

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This research study assembly process of a study of Wood Joints with Motion Time Study MTM-2 (Methods Time Measurement-2) and DFA (Design for Assembly) an assessment of the ability to assembly in the Feeding and Fitting. with LUCAS Assembly Evaluation Method for the results of the assessment and find the good-bad points of the assessment was applied. Wood Joint Index for this analysis is the feeding and fitting should not exceed 2.5 The pivot of the three groups in terms of feeding Index did not exceed 2.5 The advantages of the assessments, when applied to the wood. In general, the nature of Wood Joints must rely on to tool help in almost all assemble of the joints. Each tool is the difficulty of performing it. And in the Entrance of the parts are in a bad score. Tolerance in the 0.2 to 0.3 mm at the Wood Joint this is limitation is that the scores of these problems. So both of these topics for Wood Joints may be more table to the assessment more accurate and led to the development process for next time.

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Klass, C. M., J. R. Couchman, and A. Woods. "Control of extracellular matrix assembly by syndecan-2 proteoglycan." Journal of Cell Science 113, no. 3 (February 1, 2000): 493–506. http://dx.doi.org/10.1242/jcs.113.3.493.

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Extracellular matrix (ECM) deposition and organization is maintained by transmembrane signaling and integrins play major roles. We now show that a second transmembrane component, syndecan-2 heparan sulfate proteoglycan, is pivotal in matrix assembly. Chinese Hamster Ovary (CHO) cells were stably transfected with full length (S2) or truncated syndecan-2 lacking the C-terminal 14 amino acids of the cytoplasmic domain (S2deltaS). No differences in the amount of matrix assembly were noted with S2 cells, but those expressing S2deltaS could not assemble laminin or fibronectin into a fibrillar matrix. The loss of matrix formation was not caused by a failure to synthesize or externalize ECM components as determined by metabolic labeling or due to differences in surface expression of alpha5 or beta1 integrin. The matrix assembly defect was at the cell surface, since S2deltaS cells also lost the ability to rearrange laminin or fibronectin substrates into fibrils and to bind exogenous fibronectin. Transfection of activated alphaIIbalphaLdeltabeta3 integrin into alpha(5)-deficient CHO B2 cells resulted in reestablishment of the previously lost fibronectin matrix. However, cotransfection of this cell line with S2deltaS could override the presence of activated integrins. These results suggest a regulatory role for syndecan-2 in matrix assembly, along with previously suggested roles for activated integrins.

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Gao, P., L. Xu, R. Lin, and H. Tan. "Effect of the pivot assembly on the dynamic behaviour of a head actuator in hard disk drives." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 215, no. 4 (April 1, 2001): 461–67. http://dx.doi.org/10.1243/0954406011520887.

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Vibration/dynamics studies have become increasingly important in the mechanical design of hard disk drives (HDDs) owing to the ever-growing demand for greater storage density and access speed. In fact, it is anticipated that it is the vibration/dynamic characteristics of HDD assemblies that will eventually pose a design limit on their performance, not the associated electronics whose designs are far more advanced. In this study, finite element analysis is used to model and investigate the dynamic behaviour of a head actuator with consideration of the effect of pivot assembly. Then, an experimental method for measuring the vibration/dynamics of the head actuator is developed using the Ometron VPI laser sensor system. The representative vibration modes that limit the servo bandwidth are identified and analysed. The effect of pivot assembly on the vibration modes of the head actuator is studied under different conditions. From the results of numerical analysis and experimental demonstration, it is shown that pivot assembly is an important factor that limits the servo bandwidth and access speed of the head actuator. Based on these studies, a new passive damping structure, which is attached to the housing of the pivot assembly, is proposed, and its feasibility for improving the dynamic behaviour of the head actuator is theoretically proved.

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Shi, Tian Ze, Deng Feng Wang, Shu Ming Chen, and Hong Liang Dong. "Optimization of Double Pivot Suspension Kingpin Axis during Steering." Applied Mechanics and Materials 551 (May 2014): 232–36. http://dx.doi.org/10.4028/www.scientific.net/amm.551.232.

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A double pivot suspension used for in-wheel motor electric vehicle was designed, and the virtual prototype model of the suspension assembly was build. The suspension parameters changed greatly during steering. In order to solve this problem, this paper proposed a non-linear response surface model to fit the relationship of suspension parameters and design variables. An optimization scheme was designed based on the response surface model. The suspension performance was improved significantly using optimized variables.

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Hirono, Masafumi. "Cartwheel assembly." Philosophical Transactions of the Royal Society B: Biological Sciences 369, no. 1650 (September 5, 2014): 20130458. http://dx.doi.org/10.1098/rstb.2013.0458.

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The cartwheel is a subcentriolar structure consisting of a central hub and nine radially arranged spokes, located at the proximal end of the centriole. It appears at the initial stage of the centriole assembly process as the first ninefold symmetrical structure. The cartwheel was first described more than 50 years ago, but it is only recently that its pivotal role in establishing the ninefold symmetry of the centriole was demonstrated. Significant progress has since been made in understanding its fine structure and assembly mechanism. Most importantly, the central part of the cartwheel, from which the ninefold symmetry originates, is shown to form by self-association of nine dimers of the protein SAS-6. This finding, together with emerging data on other components of the cartwheel, has opened new avenues in centrosome biology.

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Yamamoto, Takaharu, Junko Mochida, Jun Kadota, Miyoko Takeda, Erfei Bi, and Kazuma Tanaka. "Initial Polarized Bud Growth by Endocytic Recycling in the Absence of Actin Cable–dependent Vesicle Transport in Yeast." Molecular Biology of the Cell 21, no. 7 (April 2010): 1237–52. http://dx.doi.org/10.1091/mbc.e09-05-0412.

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The assembly of filamentous actin is essential for polarized bud growth in budding yeast. Actin cables, which are assembled by the formins Bni1p and Bnr1p, are thought to be the only actin structures that are essential for budding. However, we found that formin or tropomyosin mutants, which lack actin cables, are still able to form a small bud. Additional mutations in components for cortical actin patches, which are assembled by the Arp2/3 complex to play a pivotal role in endocytic vesicle formation, inhibited this budding. Genes involved in endocytic recycling were also required for small-bud formation in actin cable-less mutants. These results suggest that budding yeast possesses a mechanism that promotes polarized growth by local recycling of endocytic vesicles. Interestingly, the type V myosin Myo2p, which was thought to use only actin cables to track, also contributed to budding in the absence of actin cables. These results suggest that some actin network may serve as the track for Myo2p-driven vesicle transport in the absence of actin cables or that Myo2p can function independent of actin filaments. Our results also show that polarity regulators including Cdc42p were still polarized in mutants defective in both actin cables and cortical actin patches, suggesting that the actin cytoskeleton does not play a major role in cortical assembly of polarity regulators in budding yeast.

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Chen, Ting, Dong Wang, and Li-Jun Wan. "Two-dimensional chiral molecular assembly on solid surfaces: formation and regulation." National Science Review 2, no. 2 (March 25, 2015): 205–16. http://dx.doi.org/10.1093/nsr/nwv012.

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Abstract The expression of chirality in 2D molecular assemblies on solid surfaces has unique features compared to the analogous process in 1D and 3D supramolecular assemblies. Understanding the formation of chiral molecular assemblies on surfaces not only provides insight into the origin and transfer of chirality in many enantioselective processes, but also aids rational design and construction of chiral architectures and materials. This present contribution reviews recent studies on how chirality is induced and expressed on the surface at different levels, both from intrinsically chiral and achiral molecules. Furthermore, we discuss the regulation effect of some pivotal factors, for example, the chemical structure, the chiral auxiliary molecules, and the assembled environments, on the expression of chirality in molecular assembly.

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Schüler, Timo, Jochen Renkel, Stephan Hobe, Moritz Susewind, Dorrit E. Jacob, Martin Panthöfer, Anja Hoffmann-Röder, Harald Paulsen, and Wolfgang Tremel. "Designed peptides for biomineral polymorph recognition: a case study for calcium carbonate." J. Mater. Chem. B 2, no. 22 (2014): 3511–18. http://dx.doi.org/10.1039/c4tb00160e.

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Peptides possess a unique ability for substrate recognition and sequence-specific self-assembly properties, and thus play a pivotal role in soft materials assembly and the mineralization of inorganic materials in natural systems.

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Noguchi, Takao, Bappaditya Roy, Daisuke Yoshihara, Youichi Tsuchiya, Tatsuhiro Yamamoto, and Seiji Shinkai. "Tailoring of the desired selectivity and the turn-on detection range in a self-assembly-based fluorescence sensory system." Chemical Science 6, no. 7 (2015): 3863–67. http://dx.doi.org/10.1039/c5sc00863h.

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A new assembly-based fluorescent sensor exhibits much improved selectivity for ATP over ADP and a broad detection range under adjusted salt conditions, providing insight into a pivotal binding mechanism in the self-assembly process.

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Janke, Ryan, Grant A. King, Martin Kupiec, and Jasper Rine. "Pivotal roles of PCNA loading and unloading in heterochromatin function." Proceedings of the National Academy of Sciences 115, no. 9 (February 13, 2018): E2030—E2039. http://dx.doi.org/10.1073/pnas.1721573115.

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In Saccharomyces cerevisiae, heterochromatin structures required for transcriptional silencing of the HML and HMR loci are duplicated in coordination with passing DNA replication forks. Despite major reorganization of chromatin structure, the heterochromatic, transcriptionally silent states of HML and HMR are successfully maintained throughout S-phase. Mutations of specific components of the replisome diminish the capacity to maintain silencing of HML and HMR through replication. Similarly, mutations in histone chaperones involved in replication-coupled nucleosome assembly reduce gene silencing. Bridging these observations, we determined that the proliferating cell nuclear antigen (PCNA) unloading activity of Elg1 was important for coordinating DNA replication forks with the process of replication-coupled nucleosome assembly to maintain silencing of HML and HMR through S-phase. Collectively, these data identified a mechanism by which chromatin reassembly is coordinated with DNA replication to maintain silencing through S-phase.

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Quinn, Caitlin M., Mingzhang Wang, Matthew P. Fritz, Brent Runge, Jinwoo Ahn, Chaoyi Xu, Juan R. Perilla, Angela M. Gronenborn, and Tatyana Polenova. "Dynamic regulation of HIV-1 capsid interaction with the restriction factor TRIM5α identified by magic-angle spinning NMR and molecular dynamics simulations." Proceedings of the National Academy of Sciences 115, no. 45 (October 17, 2018): 11519–24. http://dx.doi.org/10.1073/pnas.1800796115.

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The host factor protein TRIM5α plays an important role in restricting the host range of HIV-1, interfering with the integrity of the HIV-1 capsid. TRIM5 triggers an antiviral innate immune response by functioning as a capsid pattern recognition receptor, although the precise mechanism by which the restriction is imposed is not completely understood. Here we used an integrated magic-angle spinning nuclear magnetic resonance and molecular dynamics simulations approach to characterize, at atomic resolution, the dynamics of the capsid’s hexameric and pentameric building blocks, and the interactions with TRIM5α in the assembled capsid. Our data indicate that assemblies in the presence of the pentameric subunits are more rigid on the microsecond to millisecond timescales than tubes containing only hexamers. This feature may be of key importance for controlling the capsid’s morphology and stability. In addition, we found that TRIM5α binding to capsid induces global rigidification and perturbs key intermolecular interfaces essential for higher-order capsid assembly, with structural and dynamic changes occurring throughout the entire CA polypeptide chain in the assembly, rather than being limited to a specific protein-protein interface. Taken together, our results suggest that TRIM5α uses several mechanisms to destabilize the capsid lattice, ultimately inducing its disassembly. Our findings add to a growing body of work indicating that dynamic allostery plays a pivotal role in capsid assembly and HIV-1 infectivity.

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Achawakorn, Khosak, Thira Jearsiripongkul, and Krairoek Fanchaeng. "The effect of HDD pivot bearing assembly process on actuator arm modal frequency." KKU ENGINEERING JOURNAL 40, no. 1 (2013): 29–34. http://dx.doi.org/10.5481/kkuenj.2013.40.1.4.

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Stramer, Brian, Severina Moreira, Tom Millard, Iwan Evans, Chieh-Yin Huang, Ola Sabet, Martin Milner, Graham Dunn, Paul Martin, and Will Wood. "Clasp-mediated microtubule bundling regulates persistent motility and contact repulsion in Drosophila macrophages in vivo." Journal of Cell Biology 189, no. 4 (May 10, 2010): 681–89. http://dx.doi.org/10.1083/jcb.200912134.

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Drosophila melanogaster macrophages are highly migratory cells that lend themselves beautifully to high resolution in vivo imaging experiments. By expressing fluorescent probes to reveal actin and microtubules, we can observe the dynamic interplay of these two cytoskeletal networks as macrophages migrate and interact with one another within a living organism. We show that before an episode of persistent motility, whether responding to developmental guidance or wound cues, macrophages assemble a polarized array of microtubules that bundle into a compass-like arm that appears to anticipate the direction of migration. Whenever cells collide with one another, their microtubule arms transiently align just before cell–cell repulsion, and we show that forcing depolymerization of microtubules by expression of Spastin leads to their defective polarity and failure to contact inhibit from one another. The same is true in orbit/clasp mutants, indicating a pivotal role for this microtubule-binding protein in the assembly and/or functioning of the microtubule arm during polarized migration and contact repulsion.

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Hbaieb, Moncef, Ahmed Kacem, and Abdelkader Krichen. "Design and characterization of an assembly to obtain a linkage pivot by crimping process." Mechanics & Industry 16, no. 2 (2015): 208. http://dx.doi.org/10.1051/meca/2014086.

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Serrano González, Javier, Manuel Burgos Payán, Jesús Manuel Riquelme Santos, and Ángel Gaspar González Rodríguez. "Optimal Micro-Siting of Weathervaning Floating Wind Turbines." Energies 14, no. 4 (February 8, 2021): 886. http://dx.doi.org/10.3390/en14040886.

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This paper presents a novel tool for optimizing floating offshore wind farms based on weathervaning turbines. This solution is grounded on the ability of the assembly (wind turbine plus floater) to self-orientate into the wind direction, as this concept is allowed to freely pivot on a single point. This is a passive yaw potential solution for floating wind farms currently in the demonstration phase. A genetic algorithm is proposed for optimizing the levelised cost of energy by determining the geographical coordinates of the pivot points (i.e., the position over which the assembly can rotate to self-orient to the incoming wind direction). A tailored evaluation module is proposed to take into account the weathervaning motion around the pivot point depending on the incoming wind direction. The results obtained show the suitability of the proposed method to solve the addressed problem under realistic conditions. Additionally, the influence of the feasible region defined by the plot and the maximum area occupied on floating offshore wind farm design are also analysed in the proposed test cases. These deployable area constraints are of great importance for the viability of this technology, as it requires more space than classical solutions anchored to a fixed point.

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Rouhier, Nicolas. "Plant glutaredoxins: pivotal players in redox biology and iron-sulphur centre assembly." New Phytologist 186, no. 2 (January 13, 2010): 365–72. http://dx.doi.org/10.1111/j.1469-8137.2009.03146.x.

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Woo, Jung A., Seung‐Eon Roh, Madepalli K. Lakshmana, and David E. Kang. "Pivotal role of RanBP9 in integrin‐dependent focal adhesion signaling and assembly." FASEB Journal 26, no. 4 (January 5, 2012): 1672–81. http://dx.doi.org/10.1096/fj.11-194423.

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Kuo, Lili, and Paul S. Masters. "The Small Envelope Protein E Is Not Essential for Murine Coronavirus Replication." Journal of Virology 77, no. 8 (April 15, 2003): 4597–608. http://dx.doi.org/10.1128/jvi.77.8.4597-4608.2003.

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ABSTRACT The importance of the small envelope (E) protein in the assembly of coronaviruses has been demonstrated in several studies. While its precise function is not clearly defined, E is a pivotal player in the morphogenesis of the virion envelope. Expression of the E protein alone results in its incorporation into vesicles that are released from cells, and the coexpression of the E protein with the membrane protein M leads to the assembly of coronavirus-like particles. We have previously generated E gene mutants of mouse hepatitis virus (MHV) that had marked defects in viral growth and produced virions that were aberrantly assembled in comparison to wild-type virions. We have now been able to obtain a viable MHV mutant in which the entire E gene, as well as the nonessential upstream genes 4 and 5a, has been deleted. This mutant (ΔE) was obtained by a targeted RNA recombination method that makes use of a powerful host range-based selection system. The ΔE mutant produces tiny plaques with an unusual morphology compared to plaques formed by wild-type MHV. Despite its low growth rate and low infectious titer, the ΔE mutant is genetically stable, showing no detectable phenotypic changes after several passages. The properties of this mutant provide further support for the importance of E protein in MHV replication, but surprisingly, they also show that E protein is not essential.

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Murray, A. P., and J. Michael McCarthy. "Determining Burmester Points from the Analysis of a Planar Platform." Journal of Mechanical Design 117, no. 2A (June 1, 1995): 303–6. http://dx.doi.org/10.1115/1.2826139.

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This paper presents a technique for determining the Burmester points of five finitely separated positions in a plane. A Burmester point is the location of the fixed pivot of an RR dyad that can reach each of the five positions. These Burmester points are obtained from a “compatibility platform” constructed from selected relative poles associated with the five specified displacements. We show that the relative position pole of two assembly configurations of this platform is a fixed pivot compatible with the five positions. An example originally presented by Sandor and Erdman is used to verify the calculations.

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Aronov, Stella, Saray Dover-Biterman, Edith Suss-Toby, Michael Shmoish, Lea Duek, and Mordechai Choder. "Pheromone-encoding mRNA is transported to the yeast mating projection by specific RNP granules." Journal of Cell Biology 209, no. 6 (June 22, 2015): 829–42. http://dx.doi.org/10.1083/jcb.201408045.

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Association of messenger RNAs with large complexes such as processing bodies (PBs) plays a pivotal role in regulating their translation and decay. Little is known about other possible functions of these assemblies. Exposure of haploid yeast cells, carrying mating type “a,” to “α pheromone” stimulates polarized growth resulting in a “shmoo” projection; it also induces synthesis of “a pheromone,” encoded by MFA2. In this paper, we show that, in response to α pheromone, MFA2 mRNA is assembled with two types of granules; both contain some canonical PB proteins, yet they differ in size, localization, motility, and sensitivity to cycloheximide. Remarkably, one type is involved in mRNA transport to the tip of the shmoo, whereas the other—in local translation in the shmoo. Normal assembly of these granules is critical for their movement, localization, and for mating. Thus, MFA2 mRNAs are transported to the shmoo tip, in complex with PB-like particles, where they are locally translated.

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Ke, Pu Chun, Marc-Antonie Sani, Feng Ding, Aleksandr Kakinen, Ibrahim Javed, Frances Separovic, Thomas P. Davis, and Raffaele Mezzenga. "Implications of peptide assemblies in amyloid diseases." Chemical Society Reviews 46, no. 21 (2017): 6492–531. http://dx.doi.org/10.1039/c7cs00372b.

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We highlight the role of molecular self-assembly in eliciting the mesoscopic and pathological properties of amyloid proteins. This knowledge is pivotal for the development of theranostics against amyloid diseases.

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Sossou, Germain, Frédéric Demoly, Ghislain Montavon, and Samuel Gomes. "An additive manufacturing oriented design approach to mechanical assemblies." Journal of Computational Design and Engineering 5, no. 1 (November 15, 2017): 3–18. http://dx.doi.org/10.1016/j.jcde.2017.11.005.

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Abstract Firstly introduced as a prototyping process, additive manufacturing (AM) is being more and more considered as a fully-edged manufacturing process. The number of AM processes, along with the range of processed materials are expanding. AM has made manufacturable shapes that were too difficult (or even impossible) to manufacture with conventional technologies. This has promoted a shift in engineering design, from conventional design for manufacturing and assembly to design for additive manufacturing (DFAM). Research efforts into the DFAM field have been mostly dedicated to part's design, which is actually a requirement for a better industrial adoption. This has given rise to topologically optimized and/or latticed designs. However, since AM is also capable of manufacturing fully functional assemblies requiring a few or no assembly operations, there is a need for DFAM methodologies tackling product's development more holistically, and which are, therefore, dedicated to assembly design. Considering all the manufacturing issues related to AM of assembly-free mechanisms and available post-processing capabilities, this paper proposes a top-down assembly design methodology for AM in a proactive manner. Such an approach, can be seen as the beginning of a shift from conventional design for assembly (DFA) to a new paradigm. From a product's concept and a selected AM technology, the approach first provides assistance in the definition of the product architecture so that both functionality and successful manufacturing (including post-processing) are ensured. Particularly, build-orientation and downstream processes' characteristics are taken into account early in the design process. Secondly, for the functional flow (energy, material, signal) to be appropriately conveyed by the right amount of matter, the methodology provides guidance into how the components can be designed in a minimalism fashion leveraging the shape complexity afforded by AM. A mechanical assembly as case study is presented to illustrate the DFAM methodology. It is found that clearances and material (be it raw unprocessed material or support structures) within them plays a pivotal role in a successful assembly's design to be additively manufactured. In addition, the methodology for components' design proves to be an efficient alternative to topology optimization. Though, the approach can be extended by considering a strategy for part consolidation and the possibility to manufacture the assemblies with more than one AM process. As regards components' design, considering anisotropy can also improved the approach. Highlights Additive manufacturing is capable of printing fully functional assemblies without any assembly operations. It is found that Design For Additive Manufacturing is currently mainly focused on part's design. A process-independent, structured and systematic method for designing assembly-free mechanisms (for AM) is proposed. Build orientation and downstream processes (including post-processing capabilities) are taken into account early in the design process. A method - based on functional flows - for part's design in a minimalist fashion, is proposed.

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Hickson, Gilles R. X., and Patrick H. O'Farrell. "Anillin: a pivotal organizer of the cytokinetic machinery." Biochemical Society Transactions 36, no. 3 (May 21, 2008): 439–41. http://dx.doi.org/10.1042/bst0360439.

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Cytokinesis is a dynamic and plastic process involving the co-ordinated regulation of many components. Accordingly, many proteins, including the putative scaffold protein anillin, localize to the cleavage furrow and are required for cytokinesis, but how they function together is poorly understood. Anillin can bind to numerous other furrow components, including F-actin, septins and myosin II, but its molecular functions are unclear. Recent data suggest that anillin participates in a previously unrecognized Rho-dependent pathway that can promote the association of anillin with the plasma membrane, septins, myosin II and microtubules. Studies using the inhibitor of F-actin assembly, Lat A (Latrunculin A), have revealed that these associations occur independently of F-actin; indeed they appear to be stabilized by the loss of F-actin. This pathway may explain previously described requirements for anillin in maintaining stable furrow positioning and for forming a stable midbody, and supports the notion that anillin is a central organizer at the hub of the cytokinetic machinery.

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Morozumi, Takuma, Ryota Matsuoka, Takashi Nakamura, and Tatsuya Nabeshima. "Solvent-dependent fac/mer-isomerization and self-assembly of triply helical complexes bearing a pivot part." Chemical Science 12, no. 22 (2021): 7720–26. http://dx.doi.org/10.1039/d1sc01529j.

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Zeng, S. "On the quasi-rigid body motion of the head actuator assembly in hard disk drives." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 216, no. 12 (December 1, 2002): 1259–62. http://dx.doi.org/10.1243/095440602321029490.

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A quasi-rigid (QR) vibration mode between 3 and 5 kHz is common in current hard disk drives (HDDs), which hinders servo bandwidth improvement and thus limits growth in the areal density (numbers of bits that can be stored per unit area) of HDDs. In this paper, a finite element (FE) model of a head actuator assembly (HAA) is developed and an experimental set-up is established to study the quasi-rigid body mode. The FE model result is compared with the experimental data. It is found that the quasi-rigid body mode is in fact a butterfly-like mode, which integrates the flexibility of the pivot assembly as well as the flexibility and the mass of the whole head actuator body.

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Zhao, Dongping, Gangfeng Wang, Jizhuang Hui, Wei Hou, and Richard David Evans. "A precision analysis method for the kinematic assembly of complex products based on equivalence of deviation source." Assembly Automation 40, no. 3 (February 12, 2020): 447–60. http://dx.doi.org/10.1108/aa-03-2019-0044.

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Purpose The assembly quality of complex products is pivotal to their lifecycle performance. Assembly precision analysis (APA) is an effective method used to check the feasibility and quality of assembly. However, there is still a need for a systematic approach to be developed for APA of kinematic mechanisms. To achieve more accurate analysis of kinematic assembly, this paper aims to propose a precision analysis method based on equivalence of the deviation source. Design/methodology/approach A unified deviation vector representation model is adopted by considering dimension deviation, geometric deviation, joint clearance and assembly deformation. Then, vector loops and vector equations are constructed, according to joint type and deviation propagation path. A combined method, using deviation accumulation and sensitivity modeling, is applied to solve the kinematic APA of complex products. Findings When using the presented method, geometric form deviation, joint clearance and assembly deformation are considered selectively during tolerance modeling. In particular, the proposed virtual link model and its orientation angle are developed to determine joint deviation. Finally, vector loops and vector equations are modeled to express deviation accumulation. Originality/value The proposed method provides a new means for the APA of complex products, considering joint clearance and assembly deformation while improving the accuracy of APA, as much as possible.

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Stüssi, Marcel. "Banning of Minarets: Addressing the Validity of a Controversial Swiss Popular Initiative." Religion & Human Rights 3, no. 2 (2008): 135–53. http://dx.doi.org/10.1163/187103208x347376.

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AbstractThe proposal to ban minarets is controversial by its very nature. On the one hand Swiss citizens are sovereign and act as the ultimate supreme authority. By their will they may seek via popular initiative to enact, revoke or alter such, and any, constitutional provision as they see fit. On the other hand there are so-called material bars to Swiss constitutional amendments—such as human rights—arising from the provisions of international law. Not surprisingly, these material bars to absolute sovereignty are fiercely contested because they mean either greater or lesser powers to the citizen and, indirectly, to the political parties. The popular initiative to ban minarets raises not only questions in respect of the relationship between domestic and international law, but also appears to challenge the legal architecture of Switzerland. The initiative may be held invalid by the Swiss General Assembly (henceforth 'General Assembly' or 'Assembly') on the grounds that it breaches the peremptory norms of international law. If this proves to be the case, the Swiss people will not be given the opportunity to vote on it. Arguably, such interference is feasible only if the material bar to initiatives is widened beyond its originally accepted scope. Apparently, the powers of the Swiss Sovereign became thereby unequivocally curbed. The relationship between Swiss domestic law and international law is pivotal also should the General Assembly declare the initiative to be valid. The people would as a consequence of the Assembly's decision possess the right to vote either for or against the initiative. But regardless of the poplar vote's outcome, the second option prima facie implies that the sovereignty of the Swiss citizens has been upheld, and concessions need only to be made by those who are either for or against the proposed ban. Yet in its international context the matter is more complex and more far-reaching than that. The first part of this paper concentrates on the question of whether it is advisable for the General Assembly to compromise the people's sovereignty by widening the original scope of peremptory norms. The second part explores what a popular vote in favour of the ban on minarets could mean in law. In order to raise the awareness of the subject matter beyond its legal dimension, the introduction and conclusion of this paper will shed specific light on the rule of law as a philosophical doctrine.

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Xia, Youyi, Tenjiao Li, Cong Ma, Chang Gao, and Jun Chen. "Au/montmorillonite/polyaniline nanoflakes: facile fabrication by self-assembly and application as catalyst." RSC Adv. 4, no. 39 (2014): 20516–20. http://dx.doi.org/10.1039/c4ra02225d.

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Hydrogen bonding between citrate-stabilized Au NPs and the PANI backbone is proposed to play a pivotal role in driving the self-assembly between Au NPs and dedoped PANI, from which a highly catalytic Au NP/PANI/MMT nanocomposite was then synthesized.

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Olson, Nathan D., Todd J. Treangen, Christopher M. Hill, Victoria Cepeda-Espinoza, Jay Ghurye, Sergey Koren, and Mihai Pop. "Metagenomic assembly through the lens of validation: recent advances in assessing and improving the quality of genomes assembled from metagenomes." Briefings in Bioinformatics 20, no. 4 (August 7, 2017): 1140–50. http://dx.doi.org/10.1093/bib/bbx098.

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Abstract Metagenomic samples are snapshots of complex ecosystems at work. They comprise hundreds of known and unknown species, contain multiple strain variants and vary greatly within and across environments. Many microbes found in microbial communities are not easily grown in culture making their DNA sequence our only clue into their evolutionary history and biological function. Metagenomic assembly is a computational process aimed at reconstructing genes and genomes from metagenomic mixtures. Current methods have made significant strides in reconstructing DNA segments comprising operons, tandem gene arrays and syntenic blocks. Shorter, higher-throughput sequencing technologies have become the de facto standard in the field. Sequencers are now able to generate billions of short reads in only a few days. Multiple metagenomic assembly strategies, pipelines and assemblers have appeared in recent years. Owing to the inherent complexity of metagenome assembly, regardless of the assembly algorithm and sequencing method, metagenome assemblies contain errors. Recent developments in assembly validation tools have played a pivotal role in improving metagenomics assemblers. Here, we survey recent progress in the field of metagenomic assembly, provide an overview of key approaches for genomic and metagenomic assembly validation and demonstrate the insights that can be derived from assemblies through the use of assembly validation strategies. We also discuss the potential for impact of long-read technologies in metagenomics. We conclude with a discussion of future challenges and opportunities in the field of metagenomic assembly and validation.

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Walton, Nick V., and Luis San Andres. "Measurements of Static Loading Versus Eccentricity in a Flexure-Pivot Tilting Pad Journal Bearing." Journal of Tribology 119, no. 2 (April 1, 1997): 297–304. http://dx.doi.org/10.1115/1.2833205.

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An experimental investigation examining the static loading characteristics of a four-pad, flexure-pivot tilting pad bearing is presented. Tests are conducted on a Fluid Film Bearing Element Test Rig for journal speeds ranging from 1800 to 4500 rpm, and applied static loads between pads to 1400 N. Results obtained from measurements of bearing eccentricities and bearing pad temperatures were compared to numerical predictions. Bearing power losses were also estimated using a simple thermal model for the bearing assembly. Comparisons between theory and experimental results indicate good correlation for measured eccentricities over the tested range of applied static loads and journal speeds. Negligible displacements in the direction orthogonal to the applied load verified the expected behavior of the test bearing over the range of operating conditions. Thermal analysis of the hearing system lead to good prediction of the bearing power losses, and indicated that the majority of the mechanical energy is transferred via convection.

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Stefanova, Maria, Olga Minevich, Stanislav Baklanov, Margarita Petukhova, Sergey Lupuleac, Boris Grigor’ev, and Michael Kokkolaras. "Convex optimization techniques in compliant assembly simulation." Optimization and Engineering 21, no. 4 (March 6, 2020): 1665–90. http://dx.doi.org/10.1007/s11081-020-09493-z.

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Abstract A special class of quadratic programming (QP) problems is considered in this paper. This class emerges in simulation of assembly of large-scale compliant parts, which involves the formulation and solution of contact problems. The considered QP problems can have up to 20,000 unknowns, the Hessian matrix is fully populated and ill-conditioned, while the matrix of constraints is sparse. Variation analysis and optimization of assembly process usually require massive computations of QP problems with slightly different input data. The following optimization methods are adapted to account for the particular features of the assembly problem: an interior point method, an active-set method, a Newton projection method, and a pivotal algorithm for the linear complementarity problems. Equivalent formulations of the QP problem are proposed with the intent of them being more amenable to the considered methods. The methods are tested and results are compared for a number of aircraft assembly simulation problems.

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García-González, Ma Carmen, Eduardo Hernández-Vázquez, Raúl E. Gordillo-Cruz, and Luis D. Miranda. "Ugi-derived dehydroalanines as a pivotal template in the diversity oriented synthesis of aza-polyheterocycles." Chemical Communications 51, no. 58 (2015): 11669–72. http://dx.doi.org/10.1039/c5cc02927a.

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Various readily available, Ugi-derived dehydroalanines were used as pivotal templates to easily and efficiently assemble diverse pharmacologically important polyheterocyclic systems through cascade palladium-catalyzed C–C bond formation processes.

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Cuthbertson, Leslie, Iain L. Mainprize, James H. Naismith, and Chris Whitfield. "Pivotal Roles of the Outer Membrane Polysaccharide Export and Polysaccharide Copolymerase Protein Families in Export of Extracellular Polysaccharides in Gram-Negative Bacteria." Microbiology and Molecular Biology Reviews 73, no. 1 (March 2009): 155–77. http://dx.doi.org/10.1128/mmbr.00024-08.

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SUMMARY Many bacteria export extracellular polysaccharides (EPS) and capsular polysaccharides (CPS). These polymers exhibit remarkably diverse structures and play important roles in the biology of free-living, commensal, and pathogenic bacteria. EPS and CPS production represents a major challenge because these high-molecular-weight hydrophilic polymers must be assembled and exported in a process spanning the envelope, without compromising the essential barrier properties of the envelope. Emerging evidence points to the existence of molecular scaffolds that perform these critical polymer-trafficking functions. Two major pathways with different polymer biosynthesis strategies are involved in the assembly of most EPS/CPS: the Wzy-dependent and ATP-binding cassette (ABC) transporter-dependent pathways. They converge in an outer membrane export step mediated by a member of the outer membrane auxiliary (OMA) protein family. OMA proteins form outer membrane efflux channels for the polymers, and here we propose the revised name outer membrane polysaccharide export (OPX) proteins. Proteins in the polysaccharide copolymerase (PCP) family have been implicated in several aspects of polymer biogenesis, but there is unequivocal evidence for some systems that PCP and OPX proteins interact to form a trans-envelope scaffold for polymer export. Understanding of the precise functions of the OPX and PCP proteins has been advanced by recent findings from biochemistry and structural biology approaches and by parallel studies of other macromolecular trafficking events. Phylogenetic analyses reported here also contribute important new insight into the distribution, structural relationships, and function of the OPX and PCP proteins. This review is intended as an update on progress in this important area of microbial cell biology.

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Machado, André, Ole Tørresen, Naoki Kabeya, Alvarina Couto, Bent Petersen, Mónica Felício, Paula Campos, et al. "“Out of the Can”: A Draft Genome Assembly, Liver Transcriptome, and Nutrigenomics of the European Sardine, Sardina pilchardus." Genes 9, no. 10 (October 9, 2018): 485. http://dx.doi.org/10.3390/genes9100485.

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Clupeiformes, such as sardines and herrings, represent an important share of worldwide fisheries. Among those, the European sardine (Sardina pilchardus, Walbaum 1792) exhibits significant commercial relevance. While the last decade showed a steady and sharp decline in capture levels, recent advances in culture husbandry represent promising research avenues. Yet, the complete absence of genomic resources from sardine imposes a severe bottleneck to understand its physiological and ecological requirements. We generated 69 Gbp of paired-end reads using Illumina HiSeq X Ten and assembled a draft genome assembly with an N50 scaffold length of 25,579 bp and BUSCO completeness of 82.1% (Actinopterygii). The estimated size of the genome ranges between 655 and 850 Mb. Additionally, we generated a relatively high-level liver transcriptome. To deliver a proof of principle of the value of this dataset, we established the presence and function of enzymes (Elovl2, Elovl5, and Fads2) that have pivotal roles in the biosynthesis of long chain polyunsaturated fatty acids, essential nutrients particularly abundant in oily fish such as sardines. Our study provides the first omics dataset from a valuable economic marine teleost species, the European sardine, representing an essential resource for their effective conservation, management, and sustainable exploitation.

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Suthaweesub, Somkid, and Arbtip Dheeravongkit. "Tolerance Ring Design in the Actuator Arm of a Hard Disk Drive Using Finite Element Analysis." Applied Mechanics and Materials 275-277 (January 2013): 716–30. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.716.

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This paper presents conceptual designs for the tolerance ring in the Hard Disk Drive (HDD) in order to reduce the total deformation of the tolerance ring and decrease the installation force during the assembly process of the actuator arm, while maintaining the natural frequency within the specification range. In this research, finite element analysis was employed to compare and analyze the installation forces, total deformations of the tolerance ring and the natural frequencies of Actuator Pivot Flex Assembly (APFA). Around its cylindrical body, the tolerance ring consists of several waves which provide rigidity for the APFA assembly to resist the axial rocking motion of the actuator arm. The idea is to decrease the contact surface area between the waves and the e-block by smoothing the contact surface of the waves along the installation direction while maintaining sufficient friction to resist the axial rocking motion. The objective of this research was to minimize the total deformation and installation force. The three input variables, i.e. width, length and height of the alternating flat curve design, were analyzed together by using the engineering optimization. The decreasing of the total deformation of the tolerance ring and installation force during APFA assembly would increase the number of cycles of the reworking process which can help increase the productivity and efficiency of HDD manufacturing.

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Afik, Ran, Ehud Zigmond, Milena Vugman, Mordehay Klepfish, Elee Shimshoni, Metsada Pasmanik-Chor, Anjana Shenoy, et al. "Tumor macrophages are pivotal constructors of tumor collagenous matrix." Journal of Experimental Medicine 213, no. 11 (October 3, 2016): 2315–31. http://dx.doi.org/10.1084/jem.20151193.

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Tumor-associated macrophages (TAMs) promote tumor development, invasion, and dissemination by various mechanisms. In this study, using an orthotopic colorectal cancer (CRC) model, we found that monocyte-derived TAMs advance tumor development by the remodeling of its extracellular matrix (ECM) composition and structure. Unbiased transcriptomic and proteomic analyses of (a) TAM-abundant and -deficient tumor tissues and (b) sorted tumor-associated and -resident colonic macrophage subpopulations defined a distinct TAM-induced ECM molecular signature composed of an ensemble of matricellular proteins and remodeling enzymes they provide to the tumor microenvironment. Remarkably, many of these ECM proteins are specifically increased in human CRC versus healthy colon. Specifically, we demonstrate that although differentiating into TAMs, monocytes up-regulate matrix-remodeling programs associated with the synthesis and assembly of collagenous ECM, specifically collagen types I, VI, and XIV. This finding was further established by advanced imaging showing that TAMs instruct the deposition, cross-linking, and linearization of collagen fibers during tumor development, especially at areas of tumor invasiveness. Finally, we show that cancer-associated fibroblasts are significantly outnumbered by TAMs in this model and that their expression of collagen XIV and I is reduced by TAM deficiency. Here, we outline a novel TAM protumoral function associated with building of the collagenous ECM niche.

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Li, Linda Xiaoyan, and Xiaogang Li. "Epigenetically Mediated Ciliogenesis and Cell Cycle Regulation, and Their Translational Potential." Cells 10, no. 7 (July 2, 2021): 1662. http://dx.doi.org/10.3390/cells10071662.

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Primary cilia biogenesis has been closely associated with cell cycle progression. Cilia assemble when cells exit the cell cycle and enter a quiescent stage at the post-mitosis phase, and disassemble before cells re-enter a new cell cycle. Studies have focused on how the cell cycle coordinates with the cilia assembly/disassembly process, and whether and how cilia biogenesis affects the cell cycle. Appropriate regulation of the functions and/or expressions of ciliary and cell-cycle-associated proteins is pivotal to maintaining bodily homeostasis. Epigenetic mechanisms, including DNA methylation and histone/chromatin modifications, are involved in the regulation of cell cycle progression and cilia biogenesis. In this review, first, we discuss how epigenetic mechanisms regulate cell cycle progression and cilia biogenesis through the regulation of DNA methylation and chromatin structures, to either promote or repress the transcription of genes associated with those processes and the modification of cytoskeleton network, including microtubule and actin. Next, we discuss the crosstalk between the cell cycle and ciliogenesis, and the involvement of epigenetic regulators in this process. In addition, we discuss cilia-dependent signaling pathways in cell cycle regulation. Understanding the mechanisms of how epigenetic regulators contribute to abnormal cell cycle regulation and ciliogenesis defects would lead to developing therapeutic strategies for the treatment of a wide variety of diseases, such as cancers, polycystic kidney disease (PKD), and other ciliopathy-associated disorders.

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Okafor, Obiora Chinedu. "Remarkable returns: the influence of a labour-led socio-economic rights movement on legislative reasoning, process and action in Nigeria, 1999–2007." Journal of Modern African Studies 47, no. 2 (May 12, 2009): 241–66. http://dx.doi.org/10.1017/s0022278x09003826.

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ABSTRACTDuring 1999–2007, a labour-led but broad-based socio-economic rights movement, which focused on a pro-poor (and therefore highly popular) anti-fuel price hike message, persuaded and/or pressured Nigeria's federal legislature, the National Assembly, to: mediate between it and the Executive Branch of Government; take it seriously enough to lobby it repeatedly; re-orient its legislative processes; explicitly oppose virtually all of the Executive Branch's fuel price hikes; and reject key anti-labour provisions in a government bill. Yet the movement did not always succeed in its efforts to influence the National Assembly. This article maps, discusses, contextualises and analyses these generally remarkable developments. It also argues that while many factors combined to facilitate or militate against the movement's impact on legislative reasoning, process and action during the relevant period, this movement's ‘mass social movement’ character was the pivotal factor that afforded it the necessary leverage to exert considerable, if limited, influence on the National Assembly.

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Noda, Kazuo, Kaori Kitagawa, Takao Miki, Masahito Horiguchi, Tomoya O. Akama, Takako Taniguchi, Hisaaki Taniguchi, et al. "A matricellular protein fibulin-4 is essential for the activation of lysyl oxidase." Science Advances 6, no. 48 (November 2020): eabc1404. http://dx.doi.org/10.1126/sciadv.abc1404.

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Fibulin-4 is a matricellular protein required for extracellular matrix (ECM) assembly. Mice deficient in fibulin-4 (Fbln4−/−) have disrupted collagen and elastin fibers and die shortly after birth from aortic and diaphragmatic rupture. The function of fibulin-4 in ECM assembly, however, remains elusive. Here, we show that fibulin-4 is required for the activity of lysyl oxidase (LOX), a copper-containing enzyme that catalyzes the covalent cross-linking of elastin and collagen. LOX produced by Fbln4−/− cells had lower activity than LOX produced by wild-type cells due to the absence of lysine tyrosyl quinone (LTQ), a unique cofactor required for LOX activity. Our studies showed that fibulin-4 is required for copper ion transfer from the copper transporter ATP7A to LOX in the trans-Golgi network (TGN), which is a necessary step for LTQ formation. These results uncover a pivotal role for fibulin-4 in the activation of LOX and, hence, in ECM assembly.

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Khan, Iqbal Akhtar. "The Pivotal Role of Lifestyle Medicine Physician in Managing Chronic Diseases." Chinese Journal of Medical Research 3, no. 3 (September 25, 2020): 89–93. http://dx.doi.org/10.37515/cjmr.091x.3307.

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Background: Chronic diseases are presently the leading cause of morbidity and mortality and are responsible for most of health care expenditure, both in wealthiest countries and those with limited resources. Aims and Objectives: To ratify the competence of skill set Lifestyle Medicine Physician in identifying multiple factors tied to individual’s health. Study Design: To define the attributes of a Lifestyle Medicine Physician. Material and Methods: The role of the Lifestyle Medicine Physician in introducing meaningful, measurable, attainable and sustainable lifestyle interventions which are acceptable, doable and enjoyable for the target group, has been described. In addition the important effect of Spirituality, in the context of the Palliative Care Guidelines of the World Health Assembly and on the increasing toll of Physician Burnout, has been highlighted. Results: Implementation of lifestyle recommendations, under the guidance of Lifestyle Medicine Physician, can significantly reduce premature disability and mortality. Conclusion: The skill set physicians who, with strong basic knowledge, would be able to identify the multiple factors tied to individual ‘s health, provide individualized advice and succefully change menance of chronic lifestyle-related diseases.

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Yang, Fan, Xiaolei Zuo, Chunhai Fan, and Xian-En Zhang. "Biomacromolecular nanostructures-based interfacial engineering: from precise assembly to precision biosensing." National Science Review 5, no. 5 (February 10, 2018): 740–55. http://dx.doi.org/10.1093/nsr/nwx134.

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Abstract Biosensors are a type of important biodevice that integrate biological recognition elements, such as enzyme, antibody and DNA, and physical or chemical transducers, which have revolutionized clinical diagnosis especially under the context of point-of-care tests. Since the performance of a biosensor depends largely on the bio–solid interface, design and engineering of the interface play a pivotal role in developing quality biosensors. Along this line, a number of strategies have been developed to improve the homogeneity of the interface or the precision in regulating the interactions between biomolecules and the interface. Especially, intense efforts have been devoted to controlling the surface chemistry, orientation of immobilization, molecular conformation and packing density of surface-confined biomolecular probes (proteins and nucleic acids). By finely tuning these surface properties, through either gene manipulation or self-assembly, one may reduce the heterogeneity of self-assembled monolayers, increase the accessibility of target molecules and decrease the binding energy barrier to realize high sensitivity and specificity. In this review, we summarize recent progress in interfacial engineering of biosensors with particular focus on the use of protein and DNA nanostructures. These biomacromolecular nanostructures with atomistic precision lead to highly regulated interfacial assemblies at the nanoscale. We further describe the potential use of the high-performance biosensors for precision diagnostics.

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Journal articles on the topic 'Pivots assembly'

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