Assembly State Research Articles

Three-Dimensional Mapping Technology for Structural Deformation during Aircraft Assembly Process

Owing to the assembly state changes during aircraft assembly processes, assembly force-deformation problem occurs. To obtain the structure shape in the product assembly process efficiently and accurately, a three-dimensional (3D) mapping technology for the structural deformation during the aircraft assembly process is proposed combined with a fiber Bragg grating (FBG) optical fiber sensor and binocular vision measurement system. First, this study established a curvature transformation model using optical fiber monitoring data, obtained the 3D spatial deformation of the product, and completed the unification of the optical fiber wavelength change and spatial 3D point coordinate heterogeneous data. Second, a mesh deformation optimization algorithm based on point-cloud optimization was established. Subsequently, the deformation effects of four mesh deformation models were compared to verify the feasibility and accuracy of HEC-Laplace, and the 3D mapping of the product structure shape in the assembly process was realized. Finally, a cantilever wing model was used to verify the deformation of different loading modes. The results show that the product structure changes can be accurately obtained through the proposed technology, thereby improving the accuracy control and overall assembly quality in the aircraft assembly process and providing a theoretical basis for intelligent aircraft assembly.

Unnaturally Distorted Hexagonal Protein Ring Alternatingly Reorganized from Two Distinct Chemically Modified Proteins.

In this study, we constructed a semiartificial protein assembly of alternating ring type, which was modified from the natural assembly state via incorporation of a synthetic component at the protein interface. For the redesign of a natural protein assembly, a scrap-and-build approach employing chemical modification was used. Two different protein dimer units were designed based on peroxiredoxin from Thermococcus kodakaraensis, which originally forms a dodecameric hexagonal ring with six homodimers. The two dimeric mutants were reorganized into a ring by reconstructing the protein-protein interactions via synthetic naphthalene moieties introduced by chemical modification. Cryo-electron microscopy revealed the formation of a uniquely shaped dodecameric hexagonal protein ring with broken symmetry, distorted from the regular hexagon of the wild-type protein. The artificially installed naphthalene moieties were arranged at the interfaces of dimer units, forming two distinct protein-protein interactions, one of which is highly unnatural. This study deciphered the potential of the chemical modification technique that constructs semiartificial protein structures and assembly hardly accessible by conventional amino acid mutations.

The Development of the Constitutional Judiciary in the Republic of North Macedonia

In the legal - constitutional theory there is no doubt that constitutionality and legality presents the basic principles on which the political and legal system of a country (state) is fulfilled. This, in other words, means that the principles and rules laid down by the highest legal - constitutional act and legal act of a country, in practice should be respected and implemented.The Constitutional Court of the Republic of North Macedonia presents very important constitutional institution, with a special constitutional position that the constitution determines it directly, which along the position defines also its competences. In the work of the Constitutional Court, the Republican Assembly or other state body, don’t have the right to influence, because the Constitutional Court exercises its activities independently without the influence of any state or other non-state organ.The effectiveness of judicial - constitutional protection depends on the standard and providing the necessary conditions for an efficient and professional judiciary. Only by raising the standard and creating better conditions will be created conditions for the real realization of the rights guaranteed by the constitution. In that way are going to be created the conditions for the constitutionality and judicial - constitutional protection. Keywords: Constitutional court, professional judiciary, institutions, rule of law, dispute DOI: 10.7176/JLPG/130-06 Publication date: March 31 st 2023

Note on the performance of parametrization strategies to determine the decay heat of PWR fuel

The behavior of fuel assembly safety properties such as decay heat is often parametrized by a set of proxy variables such as burnup and by categorical variables like UOX or MOX. The standards ANS5.1 and DIN-25463 are examples of this strategy. They face the challenge to accurately approximate a wide range of possible fuel assembly states which occur in practice because they traditionally do not follow the nuclide vector evolution with a detailed microscopic model. While burnup is widely regarded as an important fuel parameter it is only an approximation or proxy for the physical relevant quantity which is the fuel nuclide vector. The performance of one of the latest and most advanced decay heat standards, DIN-25463-2014, is compared with Studsvik’s best-estimate code SSP SNF which uses a state-of-the-art microscopic model. Both the differences in initial nuclide vector after irradiation and the differences in decay heat between 1 s and 60 years are analyzed. Comparisons with realistic PWR core fuel inventories show that the margin between SSP SNF and DIN-25463-2014 varies in a range ±5% which is a manifestation of the challenge to accurately approximate the fuel state without detailed microscopic model. Given today’s small compute footprint of best-estimate codes for decay heat determination we conclude that parametrization strategies have little advantage except for applications like system codes used in transient analyses.

Single‐Crystal Superstructures via Hierarchical Assemblies of Giant Rubik's Cubes as Tertiary Building Units

AbstractIntricate superstructures possess unusual structural features and promising applications. The preparation of superstructures with single‐crystalline nature are conducive to understanding the structure–property relationship, however, remains an intriguing challenge. Herein we put forward a new hierarchical assembly strategy towards rational and precise construction of intricate single‐crystal superstructures. Firstly, two unprecedented superclusters in Rubik's cube's form with a size of ≈2×2×2 nm3are constructed by aggregation of eight {Pr4Sb12} oxohalide clusters as secondary building units (SBUs). Then, the Rubik's cubes further act as isolable tertiary building units (TBUs) to assemble diversified single‐crystal superstructures. Importantly, intermediate assembly states are captured, which helps illustrate the evolution of TBU‐based superstructures and thus provides a profound understanding of the assembly process of superstructures at the atomic level.

Single-crystal superstructures via hierarchical assemblies of giant Rubik's cubes as tertiary building units.

Intricate superstructures possess unusual structural features and promising applications. The preparation of superstructures with single-crystalline nature are conducive to understanding the structure-property relationship, however, remains an intriguing challenge. Herein we put forward a new hierarchical assembly strategy towards rational and precise construction of intricate single-crystal superstructures. Firstly, two unprecedented superclusters in Rubik's cube's form with a size of ~ 2 × 2 × 2 nm3 are constructed by aggregation of eight {Pr4Sb12} oxohalide clusters as secondary building units (SBUs). Then, the Rubik's cubes further act as isolable tertiary building units (TBUs) to assemble diversified single-crystal superstructures. Importantly, intermediate assembly states are captured, which helps illustrate the evolution of TBU-based superstructures and thus provides a profound understanding of the assembly process of superstructures at the atomic level.

Long-range corrected fragment molecular orbital density functional tight-binding method for excited states in large molecular systems.

Herein, we present a new method to efficiently calculate electronically excited states in large molecular assemblies, consisting of hundreds of molecules. For this purpose, we combine the long-range corrected tight-binding density functional fragment molecular orbital method (FMO-LC-DFTB) with an excitonic Hamiltonian, which is constructed in the basis of locally excited and charge-transfer configuration state functions calculated for embedded monomers and dimers and accounts explicitly for the electronic coupling between all types of excitons. We first evaluate both the accuracy and efficiency of our fragmentation approach for molecular dimers and aggregates by comparing it with the full LC-TD-DFTB method. The comparison of the calculated spectra of an anthracene cluster shows a very good agreement between our method and the LC-TD-DFTB reference. The effective computational scaling of our method has been explored for anthracene clusters and for perylene bisimide aggregates. We demonstrate the applicability of our method by the calculation of the excited state properties of pentacene crystal models consisting of up to 319 molecules. Furthermore, the participation ratio of the monomer fragments to the excited states is analyzed by the calculation of natural transition orbital participation numbers, which are verified by the hole and particle density for a chosen pentacene cluster. The use of our FMO-LC-TDDFTB method will allow for future studies of excitonic dynamics and charge transport to be performed on complex molecular systems consisting of thousands of atoms.

Activation of L-lactate oxidase by the formation of enzyme assemblies through liquid–liquid phase separation

The assembly state of enzymes is gaining interest as a mechanism for regulating the function of enzymes in living cells. One of the current topics in enzymology is the relationship between enzyme activity and the assembly state due to liquid–liquid phase separation. In this study, we demonstrated enzyme activation via the formation of enzyme assemblies using L-lactate oxidase (LOX). LOX formed hundreds of nanometer-scale assemblies with poly-L-lysine (PLL). In the presence of ammonium sulfate, the LOX-PLL clusters formed micrometer-scale liquid droplets. The enzyme activities of LOX in clusters and droplets were one order of magnitude higher than those in the dispersed state, owing to a decrease in KM and an increase in kcat. Moreover, the clusters exhibited a higher activation effect than the droplets. In addition, the conformation of LOX changed in the clusters, resulting in increased enzyme activation. Understanding enzyme activation and assembly states provides important information regarding enzyme function in living cells, in addition to biotechnology applications.

A novel collaborative optimization assembly process method for multi-performance of aeroengine rotors

In the assembly process of aeroengine, the aeroengines have been rejected at pass-off test for high vibration of high-pressure rotor under the condition of meeting the geometric accuracy. Repeated disassembly and trial assembly will lead to interface damage, which will affect the safety and reliability of the engine. Therefore, a multi-objective collaborative optimization process method for geometric accuracy and dynamic performance is put forward based on the practical engineering problems. In the proposed method, the primal problem firstly reveals the transfer mechanism of coaxiality and unbalance of rotor system, and the prediction model of the coaxiality and unbalance of the rotor system was established. Then, combined with the high-precision reduced-order model of aeroengine high-pressure combined rotor, the system vibration responses under different assembly states are obtained. Finally, a multi-objective collaborative optimization assembly process method considering coaxiality, unbalance and vibration response is obtained. The results show that the collaborative optimization process method considering assembly accuracy and dynamic performance is the optimal assembly strategy, which can reduce the vibration amplitude of the key nodes of the rotor system while ensuring high assembly accuracy and achieve the low-level vibration of the rotor system.

On the choice of the most suitable indicator for the assembly state of dark matter haloes through cosmic time

ABSTRACT The dynamical state and morphological features of galaxies and galaxy clusters, and their high-redshift precursors, are tightly connected with their assembly history, encoding crucial information about the formation and evolution of such cosmic structures. As a first step towards finding an optimal indicator of the assembly state of observed structures, we use a cosmological simulation of a moderate volume to critically examine the best definition of an indicator that is able to discriminate dark matter haloes undergoing mergers and/or strong accretion from haloes experimenting a relaxed evolution. Using a combination of centre offset, virial ratio, mean radial velocity, sparsity, and ellipticity of the dark matter halo, we study how the thresholds on these parameters, as well as their relative weights, should evolve with redshift to provide the best classification possible. This allows us to split a sample of haloes in a totally relaxed, a marginally relaxed and an unrelaxed subsamples. The resulting classification strongly correlates with the merging activity obtained from the analysis of complete merger trees extracted from whole simulation data. The results on how the different indicators depend on redshift and halo mass, and their optimal combination to better match the true assembly history of haloes, could constitute relevant hints to find a suitable set of indicators applicable to observational data.

Molecular Insights into a Novel Cu(I)-Sensitive ArsR/SmtB Family Repressor in Extremophile Acidithiobacillus caldus.

Acidithiobacillus caldus is a common bioleaching bacterium that is inevitably exposed to extreme copper stress in leachates. The ArsR/SmtB family of metalloregulatory repressors regulates homeostasis and resistance in bacteria by specifically responding to metals. Here, we characterized A. caldus Cu(I)-sensitive repressor (AcsR) and gained molecular insights into this new member of the ArsR/SmtB family. Transcriptional analysis indicated that the promoter (PIII) of acsR was highly active in Escherichia coli but inhibited upon AcsR binding to the PIII-acsR region. Size exclusion chromatography and circular dichroism spectra revealed that CuI-AcsR shared an identical assembly state with apo-AcsR, as a dimer with fewer α helices, more extended strands, and more β turns. Mutation of the cysteine site in AcsR did not affect its assembly state. Copper(I) titrations revealed that apo-AcsR bound two Cu(I) molecules per monomer in vitro with an average dissociation constant (KD) for bicinchoninic acid competition of 2.55 × 10-9 M. Site-directed mutation of putative Cu(I)-binding ligands in AcsR showed that replacing Cys64 with Ala reduces copper binding ability from two Cu(I) molecules per monomer to one, with an average KD of 6.05 × 10-9 M. Electrophoretic mobility shift assays revealed that apo-AcsR has high affinity for the 12-2-12 imperfect inverted repeats P2245 and P2270 in the acsR gene cluster and that Cu-loaded AcsR had lower affinity for DNA fragments than apo-AcsR. We developed a hypothetical working model of AcsR to better understand Cu resistance mechanisms in A. caldus. IMPORTANCE Copper (Cu) resistance among various microorganisms is attracting interest. The chemolithoautotrophic bacterium A. caldus, which can tolerate extreme copper stress (≥10 g/L Cu ions), is typically used to bioleach chalcopyrite (CuFeS2). Understanding of Cu resistance in A. caldus is limited due to scant investigation and the absence of efficient gene manipulation tools. Here, we characterized a new member of the ArsR/SmtB family of prokaryotic metalloregulatory transcriptional proteins that repress operons linked to stress-inducing concentrations of heavy metal ions. This protein can bind two Cu(I) molecules per monomer and negatively regulate its gene cluster. Members of the ArsR/SmtB family have not been investigated in A. caldus until now. The discovery of this novel protein enriches understanding of Cu homeostasis in A. caldus.

RanBP9 controls the oligomeric state of CTLH complex assemblies

The CTLH (C-terminal to lissencephaly-1 homology motif) complex is a multisubunit RING E3 ligase with poorly defined substrate specificity and flexible subunit composition. Two key subunits, muskelin and Wdr26, specify two alternative CTLH complexes that differ in quaternary structure, thereby allowing the E3 ligase to presumably target different substrates. With the aid of different biophysical and biochemical techniques, we characterized CTLH complex assembly pathways, focusing not only on Wdr26 and muskelin but also on RanBP9, Twa1, and Armc8β subunits, which are critical to establish the scaffold of this E3 ligase. We demonstrate that the ability of muskelin to tetramerize and the assembly of Wdr26 into dimers define mutually exclusive oligomerization modules that compete with nanomolar affinity for RanBP9 binding. The remaining scaffolding subunits, Armc8β and Twa1, strongly interact with each other and with RanBP9, again with nanomolar affinity. Our data demonstrate that RanBP9 organizes subunit assembly and prevents higher order oligomerization of dimeric Wdr26 and the Armc8β-Twa1 heterodimer through its tight binding. Combined, our studies define alternative assembly pathways of the CTLH complex and elucidate the role of RanBP9 in governing differential oligomeric assemblies, thereby advancing our mechanistic understanding of CTLH complex architectures.

Practical implementation of research on the introduction of on-board meters-indicators for monitoring the technical condition of tractors

Reducing the excess costs of the consumer due to timely maintenance and increasing the efficiency of detecting deviations in technical condition to improve operational reliability is an important task in improving the efficiency of using energy-saturated tractors of domestic production. In order to promptly provide initial information on the degree of use and the current state of resource-determining parts and assemblies, as well as to increase the controllability and adaptability to diagnosis, indicator counters integrated into the design of tractors are used. Diagnostics and information collection allows us to prevent failures and minimize costs under the conditions of branded service, as well as to monitor the current state of equipment that is under warranty or under lease. In the production of energy-saturated tractors most of the main components and aggregates in the JSC "St. Petersburg Tractor Plant" transmissions are made independently, with the exception of bearings and friction discs. Therefore, in order to increase the operational reliability of the tractor as a whole the proposals for the development of indicator counters were carried out primarily to increase the controllability and adaptability to the diagnosis of power transmissions, as the most relevant for minimizing the costs of the manufacturer, leasing company, and end user. Producing plants, research teams and individual laboratories are engaged in research to solve problems of increasing the resource of agricultural machines and tractors. However, the main indicators of the reliability of agricultural machinery increase with low dynamics, and the cost of maintaining machines increases sharply in the post-warranty period of operation [1-3].

Systematic Analysis of Assembly Intermediates in Yeast to Decipher the Mitoribosome Assembly Pathway.

Studies of yeast mitoribosome assembly have been historically hampered by the difficulty of generating mitoribosome protein-coding gene deletion strains with a stable mitochondrial genome. The identification of mitochondrial DNA-stabilizing approaches allows for the generation of a complete set of yeast deletion strains covering all mitoribosome proteins and known assembly factors. These strains can be used to analyze the integrity and assembly state of mitoribosomes by determining the sedimentation profile of these structures by sucrose gradient centrifugation of mitochondrial extracts, coupled to mass spectrometry analysis of mitoribosome composition. Subsequent hierarchical cluster analysis of mitoribosome subassemblies accumulated in mutant strains reveals details regarding the order of protein association during the mitoribosome biogenetic process. These strains also allow the expression of truncated protein variants to probe the role of mitochondrion-specific protein extensions, the relevance of protein cofactors, or the importance of RNA-protein interactions in functional sites of the mitoribosome. In this chapter, we will detail the methodology involved in these studies.

π-Electronic ion pairs: building blocks for supramolecular nanoarchitectonics viaiπ-iπ interactions.

The pairing of charged π-electronic systems and their ordered arrangement have been achieved by iπ-iπ interactions that are derived from synergetically worked electrostatic and dispersion forces. Charged π-electronic systems that provide ion pairs as building blocks for assemblies have been prepared by diverse strategies for introducing charge in the core π-electronic systems. One method to prepare charged π-electronic systems is the use of covalent bonding that makes π-electronic ions and valence-mismatched metal complexes as well as protonated and deprotonated states. Noncovalent ion complexation is another method used to create π-electronic ions, particularly for anion binding, producing negatively charged π-electronic systems. Charged π-electronic systems afford various ion pairs, consisting of both cationic and anionic π-systems, depending on their combinations. Geometries and electronic states of the constituents in π-electronic ion pairs affect the photophysical properties and assembling modes. Recent progress in π-electronic ion pairs has revealed intriguing characteristics, including the transformation into radical pairs through electron transfer and the magnetic properties influenced by the countercations. Furthermore, the assembly states exhibit diversity as observed in crystals and soft materials including liquid-crystal mesophases. While the chemistry of ion pairs (salts) is well-established, the field of π-electronic ion pairs is relatively new; however, it holds great promise for future applications in novel materials and devices.

Phosphates form spectroscopically dark state assemblies in common aqueous solutions

Phosphates and polyphosphates play ubiquitous roles in biology as integral structural components of cell membranes and bone, or as vehicles of energy storage via adenosine triphosphate and phosphocreatine. The solution phase space of phosphate species appears more complex than previously known. We present nuclear magnetic resonance (NMR) and cryogenic transmission electron microscopy (cryo-TEM) experiments that suggest phosphate species including orthophosphates, pyrophosphates, and adenosine phosphates associate into dynamic assemblies in dilute solutions that are spectroscopically "dark." Cryo-TEM provides visual evidence of the formation of spherical assemblies tens of nanometers in size, while NMR indicates that a majority population of phosphates remain as unassociated ions in exchange with spectroscopically invisible assemblies. The formation of these assemblies is reversibly and entropically driven by the partial dehydration of phosphate groups, as verified by diffusion-ordered spectroscopy (DOSY), indicating a thermodynamic state of assembly held together by multivalent interactions between the phosphates. Molecular dynamics simulations further corroborate that orthophosphates readily cluster in aqueous solutions. This study presents the surprising discovery that phosphate-containing molecules, ubiquitously present in the biological milieu, can readily form dynamic assemblies under a wide range of commonly used solution conditions, highlighting a hitherto unreported property of phosphate's native state in biological solutions.

Characterizing Heterogeneous Mixtures of Assembled States of the Tobacco Mosaic Virus Using Charge Detection Mass Spectrometry.

The tobacco mosaic viral capsid protein (TMV) is a frequent target for derivatization for myriad applications, including drug delivery, biosensing, and light harvesting. However, solutions of the stacked disk assembly state of TMV are difficult to characterize quantitatively due to their large size and multiple assembled states. Charge detection mass spectrometry (CDMS) addresses the need to characterize heterogeneous populations of large protein complexes in solution quickly and accurately. Using CDMS, previously unobserved assembly states of TMV, including 16-monomer disks and odd-numbered disk stacks, have been characterized. We additionally employed a peptide-protein conjugation reaction in conjunction with CDMS to demonstrate that modified TMV proteins do not redistribute between disks. Finally, this technique was used to discriminate between protein complexes of near-identical mass but different configurations. We have gained a greater understanding of the behavior of TMV, a protein used across a broad variety of fields and applications, in the solution state.

Software Package for Remote Diagnostics of Agricultural Machinery Condition

Artificial intelligence is stated to be more and more widely used in agriculture, as well as for the diagnostics of the agricultural machinery condition. It was noted that in besides software, new computing devices are developed that enable processing and storing large amounts of data. (Research purpose) To create a neural network-based software package for remote diagnostics of the limit state of machinery individual components and assemblies. (Materials and methods) Foreign studies within the problem area were analysed. It was found out that for data collection for artificial intelligence there exist STM32 and Arduino microcontroller-based devices, and the Nvidia CUDA (Compute Unified Device Architecture) hardware and software platform is used. For the software was developed in the C / C ++ programming language, and the MS SQL Server database were used as a repository. The general software is emphasized to be able to run on all major operating systems such as Windows, Mac OS, Linux. The role of neural network is argued to be important since it integrated all program blocks and provides its own analysis. (Results and discussion) The information from the diagnostics devices is accumulated in a database. The neural network created on the basis of this database is constantly learning and simultaneously analyzing incoming data in real time, automatically issuing its recommendations. It was found that the neural network created by the employees of the Federal Scientific Agroengineering Center VIM has more functional options, for example, it is able to work directly with devices and conduct a more detailed technical analysis. (Conclusions) A neural network for equipment condition diagnostics was created, which increases the efficiency of decision-making in case of repair, and improves forecast and predictability. The criteria for equipment operation were proposed.

Development of the fatigue life model for plastic gears of automotive actuators under vibration

In this research, a series of analysis and validation were conducted for estimating the fatigue life of plastic gears. A jig for depicting assembly state in vehicle actuators was made based on failure mechanism analysis. A vibration test for detecting the resonance frequency was performed using a frequency range specified in the ISO standard and it is confirmed that a resonance point occurs within a range generated by an engine operation. Finite element analysis was conducted to obtain the maximum stress in the vibration test applied with a sinusoidal sweep signal and the cycles to failure were calculated through the accelerated testing. The fatigue life model for plastic gears was established by deriving an S-N curve on the relation between stress and cycles to failure. The purpose of this study is to propose a design guideline for improving the reliability of vehicle actuators through the establishment of a fatigue life model for the elemental components.

Improving the accuracy of decoding monkey brain–machine interface data by estimating the state of unobserved cell assemblies

BackgroundThe brain–machine interface is a technology that has been used for improving the quality of life of individuals with physical disabilities and also healthy individuals. It is important to improve the methods used for decoding the brain–machine interface data as the accuracy and speed of movements achieved using the existing technology are not comparable to the normal body. Comparison with the existing methodDecoding of brain–machine interface data using the proposed method resulted in improved decoding accuracy compared to the existing method. ConclusionsThe results demonstrated the usefulness of cell assembly state estimation method for decoding the brain–machine interface data. New MethodWe incorporated a novel method of estimating cell assembly states using spike trains with the existing decoding method that used only firing rate data. Synaptic connectivity pattern was used as feature values in addition to firing rate. Publicly available monkey brain–machine interface datasets were used in the study. ResultsAs long as the decoding was successful, the root mean square error of the proposed method was significantly smaller than the existing method. Artificial neural netowork-based decoding method resulted in more stable decoding, and also improved the decoding accuracy due to incorporation of synaptic connectivity pattern.