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A cable‐stayed footbridge for pedestrians and cyclists is situated in post‐industrial landscape Lover Vitkovice Area (DOV) of Ostrava. The bridge has two independent sections, 84,3 m and 68,3 m long that leads across the Ostravice river and the railway corridor directly towards the recent blast furnace. The bearing structure consists of outer lattice trusses and the lower steel orthotropic deck and is characterised by outstanding variable shape created by architect. The bridge's deck is supported by three and two pairs of cables, which run directly from top of the middle stiff pylon. Cables are connected to bottom chords of the structure by cylindrical fork with threaded rod and the tie rod structural system with rolled thread (turnbuckles, forks with pin and conical lock covers). The paper describes manufacturing, erection and pre‐stressing procedure, dynamic properties and design and installation of tuned mass dampers. [ABSTRACT FROM AUTHOR]

A crimping and pultruding forming process for truss rods using Carbon Fiber (CF)/Polyether–Ether–Ketone (PEEK) prepreg tape as the raw material is proposed to address the problem of continuous manufacturing of space trusses on orbit. The proposed process provides material rods for continuous truss manufacturing. Through numerical simulation and experimental verification, the effects of relevant parameters on the forming process are determined, an efficient method of rod curl pultrusion, in-rail, equal material forming is proposed, and the structural configuration of the rod curl pultrusion forming mold is determined. The equivalent macroscopic mechanical properties of unidirectional CF/PEEK prepreg strips are considered, and the rod-forming process is investigated. Rod samples with different process parameters are prepared, and several tests are conducted on them. The results show that the forming load pull is negatively correlated with the temperature at the same forming speed, and forming speed is positively correlated with the forming load pull at a certain temperature. Temperature and speed affect the surface quality of the rod, the density of the material filling, and the mechanical properties of the rod. The optimal forming process parameters are determined through numerical simulation and experimental verification. The developed molding technology has the advantages of high efficiency, low energy consumption, and high integration. It reduces manufacturing costs and improves manufacturing efficiency, so it can serve as a new and effective solution for the manufacturing of high-performance truss rods in the aerospace field. [ABSTRACT FROM AUTHOR]

Proline substitutions within the coiled-coil rod region of the ß-myosin gene (MYH7) are the predominant mutations causing Laing distal myopathy (MPD1), an autosomal dominant disorder characterized by progressive weakness of distal/proximal muscles. We report that the MDP1 mutation R1500P, studied in what we believe to be the first mouse model for the disease, adversely affected myosin motor activity despite being in the structural rod domain that directs thick filament assembly. Contractility experiments carried out on isolated mutant muscles, myofibrils, and myofibers identified muscle fatigue and weakness phenotypes, an increased rate of actin-myosin detachment, and a conformational shift of the myosin heads toward the more reactive disordered relaxed (DRX) state, causing hypercontractility and greater ATP consumption. Similarly, molecular analysis of muscle biopsies from patients with MPD1 revealed a significant increase in sarcomeric DRX content, as observed in a subset of myosin motor domain mutations causing hypertrophic cardiomyopathy. Finally, oral administration of MYK-581, a small molecule that decreases the population of heads in the DRX configuration, significantly improved the limited running capacity of the R1500P-transgenic mice and corrected the increased DRX state of the myofibrils from patients. These studies provide evidence of the molecular pathogenesis of proline rod mutations and lay the groundwork for the therapeutic advancement of myosin modulators. [ABSTRACT FROM AUTHOR]

Large cross-section tunnel construction induces ground surface settlements, potentially endangering both subterranean projects and nearby above-ground structures. A novel tunnel construction method, known as the suspension method, is introduced in this paper to mitigate surface settlement. The suspension method employs vertical tie rods to establish a structural connection between the initial tunnel support system and the surface steel beam, thereby exerting effective control settlements. To analyze the performance of the proposed method, systematic numerical simulations were conducted based on the practical engineering of Harbin Subway Line 3. The surface settlement and vault settlement characteristics during construction are investigated. The results show a gradual increment in both surface and vault settlement throughout the construction process, culminating in a stabilized state upon the completion of construction. In addition, compared to the double-side drift method and the Cross Diaphragm Method (CRD) method, the suspension method can obviously reduce the surface settlement and vault settlement. Moreover, the surface settlements and the axial force of tie rods were continuously monitored during the construction process at the trial tunnel block. These specific monitoring measurements are illustrated in comparison to numerical analysis results. The monitored results show great agreement with the numerical predictions, confirming the success of the project. This research can serve as a valuable practical reference for similar projects, offering insights and guidance for addressing ground surface settlements and enhancing construction safety in the domain of large cross-section tunneling. [ABSTRACT FROM AUTHOR]

The aim of this study is to examine the deformation response of a four-cylinder reciprocating engine. The model of the engine was done through Autodesk Fusion 360®, while the simulation and analysis were conducted using the finite element analysis backend, Autodesk Nastran solver®. The engine assembly was subjected to a multibody dynamics study as well as a thermodynamic reaction of air-fuel mixture in the cylinder. A connecting rod was examined from the standpoint of component design to see how the maximum stress changed with crankshaft rotation. To start the engine, several crankshaft speeds were used, and the multibody simulation was carried out for 0.16s. The output from the simulation is used as surrogated data for the intelligent system modelling. A considerable degree of agreement was observed between simulation results and predicted values, demonstrating the reliability and accuracy of the model. Furthermore, it was shown that the Isection region of the connecting rod receives the maximum stress for both materials. It is essential to build this area with more strength as a result. The Von Mises stress of AlSiC is consistently lower than its yield strength, at 5.5MPa compared to 43MPa. Aluminum has a Von Mises stress of 3.5MPa, far lower than its yield strength of 276MPa. Both materials had stress levels below their yield strengths, ensuring connecting rod structural integrity. The primary factor influencing the engine's distortion profile and peak values was found to be engine torque. The findings might serve as a springboard for more research and development in this area and advance our understanding of engine behavior. [ABSTRACT FROM AUTHOR]

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To date, limited research has been conducted comparing the effects of different grinding media shapes on milling kinetics, load behaviour, and mill power draw. However, no research has explored their impact on lifter functionality. This study aims to bridge this knowledge gap by investigating the influence of grinding media shape on the lateral movement of the charge (comprising grinding media and material). This analysis involves examining specific breakage rate parameters in a laboratory dry rod mill, shedding light on how grinding media can function as lifters. In this investigation, two types of grinding media, namely simple and grooved rods, were compared. The specific breakage rate parameters were determined using the Austin model. The values associated with the µ parameter, which indicates an increase in the lifting of grinding media with its rise and a corresponding decrease in the specific rate of breakage, were found to be 3758.76 and 4144.63 for simple and grooved rods, respectively. The results demonstrate that, even though grooved rods exhibit a lower specific breakage rate than simple rods, they exhibit strong lifter characteristics. Specifically, they induce a pronounced cataracting effect in the charge. [ABSTRACT FROM AUTHOR]

Rice is the second most important cereal in the world after wheat. Threshing is one of the most essential steps in the rice harvesting process. Previously, the drum rod toothed longitudinal axial-flow threshing device has been designed to reduce the blockage of the thresher and threshing power consumption. Specifically, the power consumption of the drum-shaped threshing cylinder can be reduced by 5% to 15% on average, compared with the traditional cylindrical one. Previous work has focused on the structural design of drum-shaped threshing cylinders. But it is still lacking in the uniformity of axial loads on the drum-shaped threshing cylinder. At the same time, the current rice combine harvester threshing and separating devices are focused mostly on the structural improvement and optimization of working parameters, with respect to the performance indicators, such as threshing power consumption, harvesting yield, entrainment loss, unthreshing rate, and crushing rate. The threshing power consumption is mostly measured directly by the power consumption detector during the bench test. Only a few studies have been reported to measure the threshing power consumption, where the axial load uniformity of the drum has been quantified to optimize the rod tooth and drum structure form. In this study, the rod teeth of a drum-shaped threshing cylinder were optimized to improve the axial load uniformity of the drum-shaped threshing cylinder for a higher reduction in power consumption. The impact mechanics model of rod tooth and rice grain was established to determine the structural parameters of the rod teeth that affected the axial load uniformity of the drum, including the diameter of the rod tooth and the threshing gap. Theoretical analysis was implemented to clarify the influence of rod tooth diameter and length on the threshing power consumption. The bending angle of the elbow rod tooth and closed bow tooth was calculated to be set at 45° for better consistency of the threshing gap. The structural parameters were determined for the axial load uniformity of drum rollers, including the rod tooth diameter (7-16 mm), and threshing gap (15-30 mm). The optimal structural parameters were determined with the smallest coefficient of variation in the axial load uniformity as an indicator. A series of simulation tests were conducted to investigate the influence of rod tooth diameter and threshing gap on the axial load uniformity of cylindrical rod tooth, elbow rod tooth, and closed bow tooth drum. The results showed that the axial load trend of the drum roller with the elbow rod tooth was more uniform than that of the cylindrical rod tooth and closed bow tooth. The optimal structural parameters of the rod teeth were 10 mm rod tooth diameter, and 25 mm threshing gap. A three-factor, three-level Box-Behnken response surface bench test was conducted with the feed rate, threshing cylinder speed, and rod tooth shape as the factors, while the threshing power as the indexes, in order to reduce the threshing power consumption. A regression model was established to optimize the working parameters for the threshing power consumption. The bench test showed that the optimal working parameters of the cylindrical rod teeth drum were achieved in the feeding rate of 1.1 kg/s, and the speed of cylinder 900 r/min under the optimal structure parameters, where the lowest power consumption was 4.61 kW. The optimal working parameters of the elbow rad tooth drum were the feeding rate of 0.95 kg/s, and the speed of cylinder 935 r/min, where the power consumption was 3.58 kW. The parameters of closed arch tooth drum were no longer optimized, due to the weak ability to transport stalks easily for the blockage. The rod tooth of the drum was optimized for the shape of the tooth of the elbow rod. The drum simulation and bench tests were carried out to verify the structure and working parameters before and after the optimization of the cylindrical and elbow rod tooth. The variation coefficient of axial load uniformity of the optimized elbow rod tooth drum was 10.34% lower than that of the cylindrical rod tooth drum. The power consumption was reduced by 7.15%, indicating that the optimized elbow rod tooth effectively reduced the threshing power consumption of the drum for the better performance of the drum. This finding can provide a strong reference to optimize the performance of small longitudinal axial flow harvesters in the hilly mountainous areas in China. [ABSTRACT FROM AUTHOR]

This research delves into enhancing concrete strength through innovative approaches, particularly the substitution of traditional components with alternative materials like silica fumes, GGBS, fly ash, granite, and marble powder. The study specifically investigates the use of marble powder in self-compacting concrete, aiming to repurpose industry waste and minimize environmental impact. Focusing on M-40 concrete, the project replaces fine aggregate with varying proportions of marble powder (0%, 5%, 10%, 15%, 20%). The research explores the feasibility of this substitution by assessing the fresh and hardened properties, including self-compaction through tests like slump flow, V-funnel, and L-box. Additionally, beams are fabricated using TMT and HYBRID rods to evaluate structural behavior under diverse loading conditions. The experiment emphasizes the practical application of marble dust, considering its impact on flow properties and structural integrity. Multiple trial mixtures undergo testing, ensuring compliance with permissible limits for slump flow, V-funnel, and L-box. The structural behavior of beams, incorporating TMT and HYBRID bars, is thoroughly examined to ascertain the effectiveness of marble dust in enhancing concrete performance. In summary, this research offers valuable insights into the sustainable integration of marble powder in selfcompacting concrete, addressing both environmental concerns and structural considerations. [ABSTRACT FROM AUTHOR]

In order to solve the problems of excessive elastic deformation and excessive inertia force existed in the drive mechanism of traditional die-cutting machine, a lightweight drive rod with full symmetrical structure is proposed as the main force bearing component of the drive mechanism based on the kinematics analysis. The elastic deformation and inertia force of the lightweight drive rod are verified by static simulation analysis, and show that the weight of the drive rod is significantly reduced under the same deformation conditions, the traditional one. Further compared with, taking the minimum elastic deformation and lightweight as the optimization objectives, the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is used to optimize the structural parameters of the drive rod. The results show that under the working conditions of 350 T die-cutting force and 125 r/min rotating speed, the elastic deformation of lightweight drive rod after structural optimization is smaller (the maximum deformation is 0.00988 mm) and the weight is lighter (27% less). The research data presented in this paper can be used as the theoretical basis for future research on die-cutting mechanism. The lightweight drive rod proposed in this study can be used in die-cutting devices with high die-cutting speed and high die-cutting accuracy. [ABSTRACT FROM AUTHOR]

An approach is proposed to assess the residual structural stresses in metal rod constructions caused by initial and current damage to the metal structure. Methods of structural mechanics are used to calculate internal forces in the rods. Based on the design analysis results, the most loaded rods of the construction are determined. Taking into account the correlation of structural parameters with stress intensity in the metal, the level of residual structural stresses is estimated from the degree of damage to the most loaded rod since the damageability of the metal structure is the main prerequisite for the occurrence of these stresses. A peculiarity of the proposed approach is that the level of residual structural stresses in the rods is estimated from the change in the metal structure parameter caused by the working stresses. Based on the relationship between the characteristics of metal hardness and stresses, the latter are estimated from the dispersion parameters of these characteristics, which are determined by the LM-hardness method and correlate with the damageability of the metal structure. Based on metal hardness measurements, a calibration plot of the structural parameter versus specimen deformation and a damageability diagram of the metal structure are constructed, establishing the relationship between the structural parameter and the corresponding stress in the metal. The numerical values of the metal structure parameter are determined for the given loading conditions of the specimen by the correlation dependence of this parameter on the strain, and the level of residual structural stresses is determined from the damageability diagram of the metal structure for certain values of the metal structure parameter. The example of a truss with parallel chords illustrates the proposed approach to assessing the level of structural residual stresses. [ABSTRACT FROM AUTHOR]

Anisotropic shape and band structure engineered into double-heterojunction nanorods (DHNRs) can improve and impart new optical/optoelectronic capabilities in colloidal quantum dot-based devices. However, the photoluminescence quantum yield of DHNRs, which is significantly lower than the near-ideal limit recently achieved in the state-of-the-art core/shell quantum dots, remains as their main limitation. Here, we examine how the photoluminescence of CdS/CdSe/ZnSe DHNRs is affected by (1) the length of the CdS seed nanorods, (2) the rod and tip diameter dependent variations in band offset, and (3) the CdSe-like islands on the sides of DHNRs that can result as a side-product of ZnSe shell growth. By understanding and optimizing these three key parameters, we demonstrate an improvement in the photoluminescence quantum yield up to 93% (up to 62% for excitation above CdS bandgap) while retaining useful shape anisotropy and the band structure design in DHNRs. [ABSTRACT FROM AUTHOR]

Clinical outcomes and overall alignment after total knee arthroplasty (TKA) depend on femoral component positioning in the sagittal and the coronal plane, making choice of the distal femoral cutting guide crucial. Currently, there is no consensus on the potential advantage of an extramedullary (EM) guide compared to an intramedullary (IM) guide in TKA. The IM guide is the most widely used system for making the distal femoral cut although evidence for its superiority over the EM guide is lacking. However, inaccuracies arising with the IM guide include location of the rod entry point in the coronal plane, femoral canal diameter, femoral bowing, and structural features of the rod. Furthermore, the invasive procedure is associated with increased risk of postoperative blood loss, thromboembolic complications, and intraoperative fractures. While the EM guide has no such difficulties, its accuracy depends on the instruments used. Studies have reported results not inferior to the IM guide and a lower number of postoperative complications. Patient-specific instrumentation (PSI) and robotic and computer-assisted TKA have achieved excellent clinical and radiographic results and can overcome the problems inherent to the IM and the EM guide. Authors performed a systematic review of the literature and proposed a narrative review to summarize the characteristics of the IM and the EM guide and compare the advantages and disadvantages of each, as well as their limitations in comparison with new technologies. Authors also expressed their expert opinion. [ABSTRACT FROM AUTHOR]

• A nonlinear multi-fault dynamic model of multi-disk rod fastening rotor system is proposed and established. • The interaction and failure mechanism of multiple faults are found for the rod fastening rotor system. • The influence rule and trend of system parameters on the dynamic characteristics are disclosed. A multi-fault nonlinear model of rod fastening rotor is proposed considering the structural properties of rod fastening and the integration of multiple factors. The nonlinear analysis is performed to present the nonlinear characteristics of gas turbine rotor system with multi faults. The fault dynamics of rod fastening rotor is exposed for interaction and failure mechanism of multiple faults. The variable parameter analysis reveals the impact of system parameters variation on vibration response in multi-fault rod fastening rotor system. Analysis results reflect that multi faults enhances the nonlinearity of the system and makes dynamic characteristics more complicated. Complex nonlinear characteristics of the dynamical system are presented under different system parameters. The multi-fault nonlinear dynamic model and the nonlinear analysis of variable parameter contribute to the fault identification and stability research in the rod fastening rotor of gas turbine, which will provide the reference for the design and application of rod fastening rotor system. [ABSTRACT FROM AUTHOR]

To reduce the heating of the Terfenol-D rod and evaluate its working efficiency, six kinds of Terfenol-D rods were designed, and the temperature field of the rods was simulated and calculated using the finite element method to obtain the temperature distribution. The results showed that the untreated rod had the highest temperature; the temperature was higher in the middle and lower at both ends; higher on the outer diameter surface; and lower on the inside. When compared to the untreated rod, the temperatures of sliced rods and slit rods decreased, and the temperature of sliced rods was lower than that of slit rods; the temperature of slit rods was higher in the middle and lower at both ends; the temperature distribution of sliced rods was more uniform relatively; the slice treatment rod had the lowest temperature and the best heat suppression effect. Three structural rods were chosen and manufactured from a total of six that were tested. It shows that the temperature of all rods was higher in the middle and lower at both ends after 30 min of operation. The actual temperature of untreated rod was 34 °C, the actual temperature of radially slit rod was 32 °C, and the actual temperature of sliced rod at both ends was 28 °C. The tested temperature distributions of three rods agreed with the calculated ones. [ABSTRACT FROM AUTHOR]

Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel method and description of creating diversified complex original building forms roofed with a number of transformed folded shell units developed on the basis of a novel reference polyhedral network and arranged according to a reference surface with the negative Gaussian curvature is presented. For that purpose, specific reference polyhedral networks is are defined as a complex material deliberately composed of many regular tetrahedrons that are arranged regularly to obtain original attractive complex general building forms. The proposed method is a significant extension of the previous method for shaping roof structures with the positive Gaussian curvature and fills existing gaps in current scientific knowledge. The extended method enables the designer to significantly increase the variety of the created complex shell roof forms and plane-walled folded elevation forms of buildings and to define the shapes of their rod structural systems. It allows one to overcome the existing significant geometric and material limitations related to shape transformations of nominally flat rectangular folded steel sheets into different shell forms. The developed extension is based on formation of a set of properly connected tetrahedra as a material determining different (a) inclination of elevation walls to the vertical, and (b) distribution of many individual warped roof shells in accordance with the properties of a regular surface with negative Gaussian curvature. A number of the adopted specific sets of division coefficients (parameters) is used for determining the entire network and its complete tetrahedra. The presented description makes it possible to adopt appropriate assumptions and data and then employ the innovative method to obtain the expected characteristics of the unconventional building form shaped. The presented three different special forms created with the help of the novel method and the appropriately selected diversified values of the division coefficients of pairs of the vertices of a polyhedral reference network, a polygonal eaves network and points of a reference surface confirm the innovative scientific nature of the obtained results. The method has to be computationally aided due to the complexity of mathematical operations and the need to visualize the designed forms. [ABSTRACT FROM AUTHOR]

Retinal cyclic nucleotide-gated (CNG) ion channels bind to intracellular cGMP and mediate visual phototransduction in photoreceptor rod and cone cells. Retinal rod CNG channels form hetero-tetramers comprised of three CNGA1 and one CNGB1 protein subunits. Cone CNG channels are similar tetramers consisting of three CNGA3 and one CNGB3 subunits. Calmodulin (CaM) binds to two distinct sites (CaM1: residues 565–587 and CaM2: residues 1120–1147) within the cytosolic domains of rod CNGB1. The binding of Ca2+-bound CaM to CNGB1 promotes the Ca2+-induced desensitization of CNG channels in retinal rods that may be important for photoreceptor light adaptation. Mutations that affect Ca2+-dependent CNG channel function are responsible for inherited forms of blindness. In this review, we propose structural models of the rod CNG channel bound to CaM that suggest how CaM might cause channel desensitization and how dysregulation of the channel may lead to retinal disease. [ABSTRACT FROM AUTHOR]

Nanofiller particles, such as carbon nanotubes or metal wires, are used in functional polymer composites to make them conduct electricity. They are often not perfectly straight cylinders but may be tortuous or exhibit kinks. Therefore we investigate the effect of shape deformations of the rod-like nanofillers on the geometric percolation threshold of the dispersion. We do this by using connect-edness percolation theory within a Parsons-Lee type of approximation, in combination with Monte Carlo integration for the average overlap volume in the isotropic fluid phase. We find that a deviation from a perfect rod-like shape has very little effect on the percolation threshold, unless the particles are strongly deformed. This demonstrates that idealized rod models are useful even for nanofillers that superficially seem imperfect. In addition, we show that for small or moderate rod deformations, the universal scaling of the percolation threshold is only weakly affected by the precise particle shape. [ABSTRACT FROM AUTHOR]

A density functional theory for the bulk phase diagram of two-dimensional orientable hard rods is proposed and tested against Monte Carlo computer simulation data. In detail, an explicit density functional is derived from fundamental mixed measure theory and freely minimized numerically for hard discorectangles. The phase diagram, which involves stable isotropic, nematic, smectic, and crystalline phases, is obtained and shows good agreement with the simulation data. Our functional is valid for a multicomponent mixture of hard particles with arbitrary convex shapes and provides a reliable starting point to explore various inhomogeneous situations of two-dimensional hard rods and their Brownian dynamics. [ABSTRACT FROM AUTHOR]

We employ a first-principles-based, force-level approach to construct the anharmonic tube confinement field for entangled fluids of rigid needles, and also for chains described at the primitive-path (PP) level in two limiting situations where chain stretch is assumed to either be completely equilibrated or unrelaxed. The influence of shear and extensional deformation and polymer orientation is determined in a nonlinear elastic limit where dissipative relaxation processes are intentionally neglected. For needles and PP-level chains, a self-consistent analysis of transverse polymer harmonic dynamical fluctuations predicts that deformation-induced orientation leads to tube weakening or widening. In contrast, for deformed polymers in which chain stretch does not relax, we find tube strengthening or compression. For all three systems, a finite maximum transverse entanglement force localizing the polymers in effective tubes is predicted. The conditions when this entanglement force can be overcome by an externally applied force associated with macroscopic deformation can be crisply defined in the nonlinear elastic limit, and the possibility of a "microscopic absolute yielding" event destroying the tube confinement can be analyzed. For needles and contour-relaxed PP chains, this force imbalance occurs at a stress of order the equilibrium shear modulus and a strain of order unity, corresponding to a mechanically fragile entanglement tube field. However, for unrelaxed stretched chains, tube compression stabilizes transverse polymer confinement, and there appears to be no force imbalance. These results collectively suggest that the crossover from elastic to irreversible viscous response requires chain retraction to initiate disentanglement. We qualitatively discuss comparisons with existing phenomenological models for nonlinear startup shear, step strain, and creep rheology experiments. [ABSTRACT FROM AUTHOR]

• Innovation in projectile rod structure: The article introduces a new design by applying a jacket material to small aspect ratio tungsten fibre/Zr-based Bulk Metallic Glass Composite. The jacket material enhances the dynamic strength of the rod during penetration, changes the rheological and interaction modes of the target material during penetration, reduces the resistance encountered during penetration, improves the penetrating performance of the rod, and mitigates the phenomenon of irrational penetration in small length-to-diameter ratio rod. This has significant implications for the engineering application of rod materials. • Innovation in experimental methods: Prior to this article, scholars analyzed the penetration performance of rod materials through macroscopic experimental methods based on the terminal damage morphology of target penetration results. This article uses microscopic analysis methods such as optical microscopy, SEM, and TEM to analyze the penetration performance and deformation mode of the rod from the perspective of penetration rheological mechanism. The experimental scale is smaller, and the experiment is more detailed. Provide a new research approach for subsequent similar studies. Enriched the research methods for this issue. • Innovation in theoretical analysis: Through theoretical deduction, this article analyzes the energy dissipation during the penetration process of two structural rods. This provides theoretical support for the design of rod structures in future research. To investigate the influence of a tungsten fibre/Zr-based bulk metallic glass matrix composite (WF/Zr-MG) jacketed with C45 steel on penetration performance, this paper presents a ballistic experiment on a semi-Infinite RHA target impacted by a composite structure rod consisting of 80 % volume fraction of WF/Zr-MG (with a tungsten fibre diameter of 0.3 mm) and a low-density jacketed material (C45 steel) with an impact velocity of 1700 ± 50 m/s. This composite structure rod is compared with an unjacketed WF/Zr-MG rod. Using optical metallography and electron microscopy, this study aims to provide a comprehensive microstructural overview of the penetration process, including the solid-state penetrator flow and the exchange interaction mode of rod and target materials. The penetration performance of the two structural rods is analysed through theoretical calculation. Results indicate that the jacketed structure not only provides radial and circumferential constraints for the WF/Zr-MG rod, improving its dynamic strength, but also serves as an exchange medium for the target material during the penetration process. This characteristic changes the exchange mode of the target material and affects the interface flow mechanism. The jacketed material also acts as a solid-state lubricant at the interface, reducing the resistance to the rod's penetration. The average penetration depth of the jacketed rod is 22 % higher than that of the unjacketed rod, and the unjacketed rod consumption per unit penetration depth accounts for 3.45 % of the initial kinetic energy. while jacketed rod was only 2.5 %, which has revealed the jacketed material enhances the rod's performance and provides it with self-lubricating characteristics. [ABSTRACT FROM AUTHOR]

Various numerical models are developed that seek to reproduce, in a simulation instance, the formation and evolution of cracks in the claddings of nuclear fuel elements. The algorithms are based on the cohesive zone method within the finite element framework. When applied to simulations involving fracture mechanics, cohesive elements have various advantages, such as not needing to know the stress state in advance, representing the nucleation of the crack, and being able to reproduce the contact between the crack surfaces after fracture, with numerous application examples for ductile materials, including metals. The models developed were included in the DIONISIO 3.0 nuclear fuel code and compared with analytical test cases, controlled tests of nuclear materials, and a large set of experimental exercises with rods subjected to steep power ramps where breakages are caused due to contact with the pellets. Similarly, these new models were used in controlled experiments where the conditions of an accident type such as a loss-of-coolant accident are reproduced, analyzing the variation of the thermohydraulic, thermomechanical, and structural parameters of a rod. [ABSTRACT FROM AUTHOR]

The transportation industry has eyes set on light weighting its products. While topology optimization aided design modifications, materials like Al, Mg, and its alloys have taken centre stage in the material swap. Solid cylindrical rods provide structural support and hence, light weighting is instead done on associated parts. However, there exists an opportunity to lightweight these cylindrical rods using centralized holes without compromising on structural integrity. Tests on materials like AZ31B, Al6065, Al7075, SS304, and mild steel showed up to 11.6% increase in compressive yield strengths and up to 5% increase in ductility. The same is discussed in this work. [ABSTRACT FROM AUTHOR]

We present a Monte Carlo simulation study of helical Yukawa rods as a model for chiral liquid crystal mesogens. To simulate the cholesteric phase, we introduce a newsimulation method that uses softwalls and self-determined boundary conditions. We observe that the isotropic-nematic phase transition is shifted to lower volume fractions with decreasing salt concentration as well as with increasing internal pitch of the rods. For particular sets of interaction parameters, the sense of the cholesteric pitch inverts, i.e., depending on concentration, mesogens of a given handedness can produce cholesteric phases of both chiral senses. [ABSTRACT FROM AUTHOR]

The equilibrium properties of hard rod monolayers are investigated in a lattice model (where position and orientation of a rod are restricted to discrete values) as well as in an off-lattice model featuring spherocylinders with continuous positional and orientational degrees of freedom. Both models are treated using density functional theory and Monte Carlo simulations. Upon increasing the density of rods in the monolayer, there is a continuous ordering of the rods along the monolayer normal ("standing up" transition). The continuous transition also persists in the case of an external potential which favors flat-lying rods in the monolayer. This behavior is found in both the lattice and the continuum models. For the lattice model, we find very good agreement between the results from the specific DFT used (lattice fundamental measure theory) and simulations. The properties of lattice fundamental measure theory are further illustrated by the phase diagrams of bulk hard rods in two and three dimensions. [ABSTRACT FROM AUTHOR]

We study the optimal packing of short, hard spherocylinders confined to lie tangential to a spherical surface, using simulated annealing and molecular dynamics simulations. For clusters of up to twelve particles, we map out the changes in the geometry of the closest-packed configuration as a function of the aspect ratio L/D, where L is the cylinder length and D the diameter of the rods. We find a rich variety of cluster structures. For larger clusters, we find that the best-packed configurations up to around 100 particles are highly dependent on the exact number of particles and aspect ratio. For even larger clusters, we find largely disordered clusters for very short rods (L/D = 0.25), while slightly longer rods (L/D = 0.5 or 1) prefer a global baseball-like geometry of smectic-like domains, similar to the behavior of large-scale nematic shells. Intriguingly, we observe that when compared to their optimal flat-plane packing, short rods adapt to the spherical geometry more efficiently than both spheres and longer rods. Our results provide predictions for experimentally realizable systems of colloidal rods trapped at the interface of emulsion droplets. [ABSTRACT FROM AUTHOR]

Rod and cone photoreceptors of the vertebrate retina utilize cGMP as the primary intracellular messenger for the visual signaling pathway that converts a light stimulus into an electrical response. cGMP metabolism in the signal-transducing photoreceptor outer segment reflects the balance of cGMP synthesis (catalyzed by guanylyl cyclase) and degradation (catalyzed by the photoreceptor phosphodiesterase, PDE6). Upon light stimulation, rapid activation of PDE6 by the heterotrimeric G-protein (transducin) triggers a dramatic drop in cGMP levels that lead to cell hyperpolarization. Following cessation of the light stimulus, the lifetime of activated PDE6 is also precisely regulated by additional processes. This review summarizes recent advances in the structural characterization of the rod and cone PDE6 catalytic and regulatory subunits in the context of previous biochemical studies of the enzymological properties and allosteric regulation of PDE6. Emphasis is given to recent advances in understanding the structural and conformational changes underlying the mechanism by which the activated transducin α-subunit binds to—and relieves inhibition of—PDE6 catalysis that is controlled by its intrinsically disordered, inhibitory γ-subunit. The role of the regulator of G-protein signaling 9–1 (RGS9-1) in regulating the lifetime of the transducin-PDE6 is also briefly covered. The therapeutic potential of pharmacological compounds acting as inhibitors or activators targeting PDE6 is discussed in the context of inherited retinal diseases resulting from mutations in rod and cone PDE6 genes as well as other inherited defects that arise from excessive cGMP accumulation in retinal photoreceptor cells. [ABSTRACT FROM AUTHOR]

Vision in dim-light conditions is triggered by photoactivation of rhodopsin, the visual pigment of rod photoreceptor cells. Rhodopsin is made of a protein, the G protein coupled receptor (GPCR) opsin, and the chromophore 11-cis-retinal. Vertebrate rod opsin is the GPCR best characterized at the atomic level of detail. Since the release of the first crystal structure 20 years ago, a huge number of structures have been released that, in combination with valuable spectroscopic determinations, unveiled most aspects of the photobleaching process. A number of spontaneous mutations of rod opsin have been found linked to vision-impairing diseases like autosomal dominant or autosomal recessive retinitis pigmentosa (adRP or arRP, respectively) and autosomal congenital stationary night blindness (adCSNB). While adCSNB is mainly caused by constitutive activation of rod opsin, RP shows more variegate determinants affecting different aspects of rod opsin function. The vast majority of missense rod opsin mutations affects folding and trafficking and is linked to adRP, an incurable disease that awaits light on its molecular structure determinants. This review article summarizes all major structural information available on vertebrate rod opsin conformational states and the insights gained so far into the structural determinants of adCSNB and adRP linked to rod opsin mutations. Strategies to design small chaperones with therapeutic potential for selected adRP rod opsin mutants will be discussed as well. [ABSTRACT FROM AUTHOR]

We theoretically investigate the pitch of lyotropic cholesteric phases composed of slender rods with steric chirality transmitted via a weak helical deformation of the backbone. In this limit, the model is amenable to analytical treatment within Onsager theory and a closed expression for the pitch versus concentration and helical shape can be derived. Within the same framework, we also briefly review the possibility of alternative types of chiral order, such as twist-bend or screw-like nematic phases, finding that cholesteric order dominates for weakly helical distortions. While long-ranged or "soft" chiral forces usually lead to a pitch decreasing linearly with concentration, steric chirality leads to a much steeper decrease of quadratic nature. This reveals a subtle link between the range of chiral intermolecular interaction and the pitch sensitivity with concentration. A much richer dependence on the thermodynamic state is revealed for polar helices where parallel and anti-parallel pair alignments along the local director are no longer equivalent. It is found that weak temperature variations may lead to dramatic changes in the pitch, despite the lyotropic nature of the assembly. [ABSTRACT FROM AUTHOR]

Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing. [ABSTRACT FROM AUTHOR]

The phenomenological model [van der Schoot et al., J. Phys. Chem. B 112, 4512 (2008)] for predicting the alignment of carbon nanotube (CNT) dispersions in thermotropic liquid crystals is extended to include the attractive interactions between CNTs. The influence of the attractive forces (described by a spatially uniform mean field) on the phase behavior and orientational properties of the mixture are analyzed. [ABSTRACT FROM AUTHOR]

The stability limits of the isotropic state of melt of rod-rod AB polydisperse diblock copolymer have been studied within weak segregation theory. The number of units in A block is assumed to be a random variable distributed by the Schulz-Zimm distribution. Inspection of the spinodal curves shows that the copolymer melt with polydisperse rigid blocks is less stable with respect to formation of the nematic and microphase separated states than the monodisperse melt. The values of ratios between strengths of isotropic and anisotropic interactions in the system strongly influences the forms of isotropic-nematic boundary curves. [ABSTRACT FROM AUTHOR]

In the last two decades, it has been demonstrated that highly nonlinear solitary waves (HNSWs) can be used in many physics and engineering applications, such as acoustic lenses, impurity detectors, and nondestructive testing. HNSWs are compact nondispersive waves that propagate in nonlinear media such as 1D chains of spherical particles. In this paper, we propose to couple an array of granular particles that support the propagation of HNSWs, to a wafer-type lead zirconate titanate (PZT) transducer in order to harvest the energy of an object tapping the array. This latter is in contact with a polycarbonate block where the nonlinear waves become linear and coalesce at a designed focal point. Here, the PZT converts the acoustic energy into electricity that powers a load resistor. The performance of this harvester is compared to a similar system where the chains are replaced by solid rods. The results demonstrate that the granular system generates more electricity. [ABSTRACT FROM AUTHOR]

Rod-like colloidal particles are known to display an isotropic-nematic phase transition on increase of concentration, as predicted already by Onsager. Both natural clay particles and synthetic rods tend to be polydisperse, however, and the question arises how to allow for this in comparing experimental observations with theory. Experimental data for a wide range of samples (both from the literature and the new results) have been collated, with aspect ratios ranging from 14 to 35. As a characteristic, the concentration is taken where half of the sample volume is nematic. Experimental data agree well with predictions for monodisperse finite aspect ratio rods. However, compared to these predictions, the width of the transition (taken as the ratio of isotropic and nematic limiting concentrations) is noticeably broadened. Still, in most cases, the transition can be characterised by a linear increase of the nematic phase volume with sample concentration. The transition width is in broad agreement with theoretical predictions for infinitely thin rods. [ABSTRACT FROM AUTHOR]

Using Monte Carlo simulation, we analyse the behaviour of two-dimensional hard rods in four different types of geometric confinement: (i) a slit pore where the particles are confined between two parallel walls with homeotropic anchoring; (ii) a hybrid slit pore formed by a planar and a homeotropic wall; square cavities that frustrate the orientational order by imposing either (iii) homeotropic or (iv) planar wall anchoring. We present results for the state diagram as a function of the packing fraction and the degree of confinement. Under extreme confinement, unexpected states appear with lower symmetries than those of the corresponding stable states in bulk, such as the formation of states that break the anchoring constraints or the symmetry imposed by the surfaces. In both types of square cavities, the particles form disclinations at intermediate densities. At high densities, however, the elastic stress is relaxed via the formation of domain walls where the director rotates abruptly by 90°, [ABSTRACT FROM AUTHOR]

The dynamical properties of a system of soft rods governed by stochastic hard collisions (SHCs) have been determined over a varying range of softness using molecular dynamics simulations in one dimension and analytic theory. The SHC model allows for interpenetration of the system's constituent particles in the simulations, generating overlapping clustering behavior analogous to the spatial structures observed in systems governed by deterministic bounded potentials. Through variation of an assigned softness parameter d, the limiting ranges of intermolecular softness are bridged, connecting the limiting ensemble behavior from hard to ideal (completely soft). Various dynamical and structural observables are measured from simulation and compared to developed theoretical values. The spatial properties are found to be well predicted by theories developed for the deterministic penetrable-sphere model with a transformation from energetic to probabilistic arguments. While the overlapping spatial structures are complex, the dynamical properties can be adequately approximated through a theory built on impulsive interactions with Enskog corrections. Our theory suggests that as the softness of interaction is varied toward the ideal limit, correlated collision processes are less important to the energy transfer mechanism, and Markovian processes dominate the evolution of the configuration space ensemble. For interaction softness close to hard limit, collision processes are highly correlated and overlapping spatial configurations give rise to entanglement of single-particle trajectories. [ABSTRACT FROM AUTHOR]

ETVS fuel assemblies containing nitride fuel rods with different structural implementation and cladding made of different materials are tested in the cores of the BN-600 and BOR-60 reactors in order to substantiate the efficiency of fuel rods with mixed uranium-plutonium nitride fuel used in sodium-cooled (BN-1200) and lead-cooled (BREST-OD-300) reactors. We report here the results of post-reactor studies of BN-600, -800, -1200 and BREST type fuel elements with a helium sublayer after irradiation to maximum burnup 7.5, 6, and 4.5% h.a., respectively, in the composition of 10 ETVS BN-600 fuel assemblies as well BREST type fuel rods with helium and lead sublayer after tests to maximum burnup 5 and 4% h.a. as fuel elements of the BREST type with a helium and lead sublayer after testing to maximum burnup 5 and 4% h.a. in the composition of two ETVS BOR-60 fuel assemblies. The obtained results confirmed that the nitride fuel rods with gas and lead sublayers and EP-823 steel cladding remain efficient at the attained test parameters and, possibly, at higher fuel burnup. [ABSTRACT FROM AUTHOR]

We study by means of molecular and Brownian dynamics simulations the influence of bending flexibility on the phase behavior and dynamics of monodisperse hard filamentous particles with an aspect ratio of 8 and persistence lengths equal to 3 and 11 times the particle length. Although our particles are much shorter, the latter corresponds to the values for wild-type and mutant fd virus particles that have been subject of a recent experimental study, where the diffusion of these particles in the nematic and smectic-A phase was investigated by means of video fluorescence microscopy [E. Pouget, E. Grelet, and M. P. Lettinga, Phys. Rev. E 84, 041704 (2011)]. In agreement with theoretical predictions and simulations, we find that for the more flexible particles (shorter persistence length) the nematic (N) to smectic-A (Sm-A) phase transition shifts to larger values of the particle density. Interestingly, we find that for the more rigid particles (larger persistence length), the smectic layer-tolayer distance decreases monotonically with increasing density, whereas for the more flexible ones, it first increases, reaches a maximum and then decreases. For our more flexible particles, we find a smectic-B phase at sufficiently high densities. Moreover, in line with experimental observations and theoretical predictions, we find heterogeneous dynamics in the Sm-A phase, in which particles hop between the smectic layers. We compare the diffusion of our two types of particle at identical values of smectic order parameter, and find that flexibility does not change the diffusive behavior of particles along the director yet significantly slows down the diffusion perpendicular to it. In our simulations, the ratio of diffusion constants along and perpendicular to the director decreases just beyond the N-Sm-A phase transition for both our stiff and more flexible particles. [ABSTRACT FROM AUTHOR]

Synapses are fundamental information processing units that rely on voltage-gated Ca2+ (Cav) channels to trigger Ca2+-dependent neurotransmitter release. Cav channels also play Ca2+-independent roles in other biological contexts, but whether they do so in axon terminals is unknown. Here, we addressed this unknown with respect to the requirement for Cav1.4 L-type channels for the formation of rod photoreceptor synapses in the retina. Using a mouse strain expressing a non-conducting mutant form of Cav1.4, we report that the Cav1.4 protein, but not its Ca2+ conductance, is required for the molecular assembly of rod synapses; however, Cav1.4 Ca2+ signals are needed for the appropriate recruitment of postsynaptic partners. Our results support a model in which presynaptic Cav channels serve both as organizers of synaptic building blocks and as sources of Ca2+ ions in building the first synapse of the visual pathway and perhaps more broadly in the nervous system. [ABSTRACT FROM AUTHOR]

Cylindrical foil liners, with foil thicknesses on the order of 400 nm, are often used in university-scale Z-pinch experiments (∼1 MA in 100 ns) to study physics relevant to inertial confinement fusion efforts on larger-scale facilities (e.g., the magnetized liner inertial fusion effort on the 25-MA Z facility at Sandia National Laboratories). The use of ultrathin foil liners typically requires a central support rod to maintain the structural integrity of the liner target assembly prior to implosion. The radius of this support rod sets a limit on the maximum convergence ratio achievable for the implosion. In recent experiments with a support rod and a pre-imposed axial magnetic field, helical instability structures in the imploding foil plasma were found to persist as the foil plasma stagnated on the rod and subsequently expanded away from the rod [Yager-Elorriaga et al., Phys. Plasmas 25(5), 056307 (2018)]. We have now used the 3D extended magnetohydrodynamics simulation code PERSEUS (which includes Hall physics) [C. E. Seyler and M. R. Martin, Phys. Plasmas 18(1), 012703 (2011)] to study these experiments. The results suggest that it is the support rod that is responsible for the helical structures persisting beyond stagnation. Furthermore, we find that as the radius of the support rod decreases (i.e., as the convergence ratio increases), the integrity and persistence of the helical modes diminish. In the limit with no support rod, we find that the structure of the final stagnation column is governed by the structure of the central precursor plasma column. These simulation results and their comparisons to experiment are presented. [ABSTRACT FROM AUTHOR]

Tie rods are structural elements that transfer axial tensile loads and are typically used on walls, vaults, arches, and buttresses in historical buildings. To verify their load-bearing capacity and identify possible structural damage risks, the forces transferred by tie rods and the corresponding stresses must be determined. However, this is often a challenging task due to the lack of project documentation for historical buildings. Uncertainties like complex boundary conditions or unknown material and geometrical properties make it hard to assess the tie rods' load level. This paper presents a methodology for the determination of axial forces in tie rods that combines on-site experimental research and a numerical model-updating technique. Along with the common approach based on a determination of the natural frequency of tie rods, this paper presents an approach based on tie rods' mode shapes. Special emphasis is placed on the boundary conditions coefficient, which is a crucial parameter in the analytical solution for axial forces determination based on the conducted on-site experiments. The method is applied in a historical building case study. [ABSTRACT FROM AUTHOR]

In structural engineering, buckling is usually associated with compressive stress and/or shortening deformation states. Recently, several works came to light alerting to the propensity of some structural systems to buckle under tension. Within this context, the present work examines the buckling and post-buckling behaviours of repetitive rods systems under tensile axial loading, and comprises three distinct parts. At first, the tensile stability behaviour of a single rigid rod with an edge section supported by a slider that is forced to follow a pre-established path, developed in the literature that lays behind us, is revisited and related to the buckling behaviour of an alternative two rods system whose buckling propensity arises from a secondary compressed bar overlapping the tensioned one. In the second part of the paper, overlapping is used to create innovative repetitive frames that buckle under tension, in the present case a sequence of lined up rigid rods connected by rotational joints. The tensile critical load shows little change as new modules are added to the system, in clear contrast with the compressive case. The tensile post-buckling behaviour is also assessed, in some cases showing original shapes, and overlapping is used to create repetitive frames with negative thermal expansion coefficient as well. In the third part of the paper, the effects of applying global gradients to the relevant mechanical properties, in the form of smooth variations of the joints rigidities and rods lengths as the module is repeated, on the stability behaviour under tension are assessed. Although these variations are smooth and kept within small values, they provoke significant changes on the tensile buckling load, on the buckling type and on the type of buckling as well. The findings pave the way to the development of innovative repetitive frames, cellular materials, polymer chains and origami structures showing original constitutive behaviours under tension. [ABSTRACT FROM AUTHOR]

We derive a one‐dimensional model for an elastic shuttle, that is, a thin rod with rounded ends and small fixed terminals, by means of an asymptotic procedure of dimension reduction. In the model, deformation of the shuttle is described by a system of ordinary differential equations with variable degenerating coefficients, and the number of the required boundary conditions at the end points of the one‐dimensional image of the rod depends on the roundness exponent m∈(0,1). Error estimates are obtained in the case m∈(0,1/4) by using an anisotropic weighted Korn inequality, which was derived in an earlier paper by the authors. We also briefly discuss boundary layer effects, which can be neglected in the case m∈(0,1/4) but play a crucial role in the formulation of the limit problem for m ≥ 1/4. [ABSTRACT FROM AUTHOR]

Single-rod electrohydraulic system is widely applied in industrial production due to high power-to-weight ratio, but it generally has a low energy efficiency and has many system states which need to be measured. Therefore, an output feedback controller with energy saving is proposed in this paper. The designed controller only needs a displacement sensor to detect the position of the single-rod cylinder; the other states of the system are estimated by extended state observer (ESO). Besides, a nonlinear disturbance observer (NDO) is introduced to estimate the external mismatched disturbance. The output feedback controller based on extended state observer and nonlinear disturbance observer has a better tracking performance compared with other controllers. In addition, a proportional relief valve (PRV) is introduced to control the supply pressure of the system. The variable supply pressure reduces the energy of throttling loss and overflow loss, which achieves energy saving of about 54% according to the simulation results. Meanwhile, the tracking error of the energy saving controller is stable at 0.1 mm. In a word, the proposed controller not only achieves energy saving but also has a satisfactory trajectory tracking performance. [ABSTRACT FROM AUTHOR]