Parallel Wires Research Articles

Parallel wire technique as a bailout for chronic total occlusion recanalization due to microcatheter over-torquing and entrapment.

Parallel wire technique as a bailout for chronic total occlusion recanalization due to microcatheter over-torquing and entrapment.

Reuse of CFRP Pultrusions in Novel Post-Tensioning Cables for Bridge Strengthening

This paper presents the development and validation of a new filament-wound CFRP sleeve and resin grout for the efficient anchorage of parallel CFRP wire bundles. Twenty-five-year-old, reused CFRP wires (recovered from two dismantled bridge cables) were examined with regard to any possible drop in strength or stiffness due to aging and then processed into two bridge strengthening cables. The new anchorage and cables were tested to their tensile capacity (giving on average 1.833 MN) in two full-scale instrumented experiments. This being successful, it gave the authors the confidence to manufacture two new 26–30 m long post-tensioning parallel-wire cables, each using 37 of the recovered CFRP wires. Both CFRP parallel-wire cables were finally successfully prestressed to 1 MN (55% of their UTS) in order to strengthen an existing bridge in the Swiss Alps over the river Ilfis in the summer of 2023. This strengthening project is described. The full-scale tests confirmed the durability and strength of the new anchorage system, and the feasibility for reusing valuable CFRP pultrusions for post-tensioning was proven by the successful bridge strengthening carried out. Finally, the project also demonstrated the sustainability potential of CFRP pultrusions. The monitoring data of this bridge project are presented and discussed.

Multiwire Position-Sensitive Neutron Detector with Two Layers of Boron-10

Multiwire position-sensitive neutron detector with two layers of boron-10 was developed to detect both thermal and fast neutrons. Sensitive dimensions of two coordinate neutron detector are 50 × 50 mm. New detector characteristics are compared with ones of 100 × 100 mm detector built earlier which we used in neutron flux spatial distribution measurement. Plane-parallel design of new detector has symmetrical structure with respect to wire anode and also includes two intermediate grids and two cathodes made of parallel wires with 2 mm pitch and two silicon substrates coated boron-10 layers of 0.003 mm thickness. Detector geometry, working gas mixture and pressure are chosen so as to ensure full absorption of secondary alpha particle from reaction with thermal neutron within detector gas medium half thickness. Neutron coordinates are determined from measured ionization loss pulse heights produced by secondary nucleus. Detector expected efficiency to thermal neutrons is about 5%. The detector can be used in small-angle and diffraction scattering setups in condensed matter physics.

Why do similar 1D-polyhedron-chain copper chloride semiconductors have 2-order-distinct luminescence quantum efficiencies?

The "green" copper halides with one-dimensional polyhedron chains are very interesting novel semiconductors. These weakly interacting parallel quantum wires (1D polyhedron chains) play key roles in their photophysical properties. Unlike Cs3Cu2I5, which has been much investigated, its homologous compounds Cs3Cu2Cl5 and CsCu2Cl3 remain less studied and their properties are controversial. Both of them are composed of specific 1D-polyhedron-chains. We report the synthesis and comparatively study the photophysical properties of the single crystals of Cs3Cu2Cl5 and CsCu2Cl3. They exhibit green and orange emissions, respectively. Surprisingly, their luminescence quantum efficiencies have a giant difference of over two orders of magnitude (96.7% vs 0.7%). The CsCu2Cl3 crystals exhibit much slower radiative transition and substantially faster nonradiative transition. The experiment in combination with the density functional theory calculation reveals that their 1D-polyhedron-chains have distinct bonding structures and degrees of distortion. This leads to different distributions of electron wave functions and different concentrations of carrier-trapping chlorine vacancies, which account for their highly contrasted quantum efficiencies. The CsCu2Cl3 and Cs3Cu2Cl5 crystals exhibit easy phase transition between each other driven by the changed temperature or ethanol erosion owing to their resembling skeleton structures of 1D polyhedral chain.

Intravascular ultrasound-guided reentry wiring with tip-detection technique for chronic total occlusion of lower extremity artery disease

BackgroundEndovascular therapy is an effective method for revascularization in lower extremity artery disease, but treating chronic total occlusion (CTO) remains challenging. This is particularly true for patients with severe calcification, poor run-off in below-the-knee arteries, or limited access sites, where even guidewire (GW) passage can be difficult and bidirectional approaches are often not feasible. The tip-detection (TD) method has been reported as a useful technique in coronary artery CTO interventions, allowing real-time visualization of the GW tip direction. Here, we applied the TD technique for peripheral CTO intervention.Case presentationCase 1 involved a 71-year-old man with a right toe ulcer. Angiography revealed total occlusion from the right anterior tibial artery (ATA) to the proximal dorsalis pedis artery. While attempting IVUS-guided parallel wiring, the GW could not advance through the intraplaque route because of severe calcification. We intentionally advanced the GW and IVUS into the subintimal space of the ATA to bypass the calcified lesion and performed IVUS-guided reentry using the TD technique in the distal ATA, where calcification was less severe. The second GW successfully passed through the intraplaque of the distal ATA and into the true lumen of the dorsalis pedis artery. Case 2 involved a 60-year-old man with bilateral intermittent claudication. Angiography revealed severe stenosis of the right common iliac artery (CIA) and CTO of the left CIA. Because of anatomical limitations and access site challenges, the antegrade approach for the left CIA was unsuccessful, and retrograde intraluminal wiring was difficult because of flexion and calcification. We advanced the GW and IVUS into the subintimal space and performed IVUS-guided reentry using the TD technique to access the true lumen of the proximal CIA. Finally, bilateral VBX stent grafts were implanted using the kissing stent technique.ConclusionsIVUS-guided reentry wiring with the TD technique may offer a useful solution for passing complex peripheral CTO lesions in cases where only a uni-directional approach is feasible.

Parallel Wire Approach for Recanalisation of Chronic Total Coronary Occlusions in a Large Contemporary Multi-Center Registry.

The parallel wire technique (PW) is a classic part of the antegrade strategy to open chronic total coronary occlusions (CTO). With modern wires and dual-lumen catheters (DLC) the approach has evolved, but this progress had not been evaluated in a contemporary registry of CTO interventions. This analysis is based on 26,589 CTO procedures performed by 36 operators with > 50 procedures annually between 2015 and 2022. The different strategies and techniques were analyzed with respect to clinical and lesion characteristics, procedural resource use and periprocedural complications. Within the antegrade approach, PW was compared to antegrade wire escalation (AWE) and antegrade-dissection re-entry (ADR). The primary antegrade approach was used in 65.9%, primary retrograde in 16.9% and a strategy change in 17.2% with a wide inter-operator variability. In primary antegrade approach, PW was applied in 10.8% and ADR in 5.3%. Lesion complexity was higher in AWE and PW than with single wire, and highest in ADR procedures, leading to more complex procedures with higher contrast and radiation usage. Complications increased with ADR, while they were similar with PW and AWE. Through the observation period PW adoption increased steadily from 6.7% to 10.7%, as the DLC use facilitating PW increased from 8.3% to 17.0% over the observation period. In this largest database of contemporary CTO PCI from Europe, PW adoption increased over time but remained low at about 10%. While there was a wide individual variety among the operators, it was a safe and successful technique.

Guide-wire and K-wire readjustment jig for osteotomy and osteosynthesis: An instrument.

Numerous orthopaedic procedures including dynamic hip screw plating and various osteotomies require placement of a reference guide pin or K wire to direct bone cuts or for drilling screw holes. Appropriate positioning of these wires is a critical component of surgery. Irrespective of whether one is a seasoned surgeon or an apprentice, these wires often need repositioning and readjustment. Parallel wire positioning is needed even during procedures like osteotomies or patellar fracture fixation. Though there are several tools available to help with accurate placement of wires and saving operating time, there are very few tools which can actually control the direction or angulation of the wire. The ones which are available are usually difficult to use, are bulky, have long attachments arms or have too many fine adjustments. We propose a device that not only directs the positioning of the parallel wires but also helps with a 360-degree correction in direction of the wrongly positioned wire. It is a multipurpose jig that can be used in patella fracture, inter-trochanteric fracture femur, fracture neck of femur, osteotomies around knee, elbow and distal femur, etc. We proposed, designed and manufactured a new device for the guide wire insertion. Our jig design has three tunnels. Two tunnels, primary and secondary run parallel to each other and the oblique tunnel runs at an angle and is positioned 7mm away from the parallel tunnel at one end and shares a common opening with the secondary tunnel on opposite end. Other similar jigs either have only parallel tunnels (primary and secondary) or an oblique tunnel which is at the far end of metal bar, making it difficult to be used to correct the angular direction of the guidewire in reference to primary or secondary wire. Using our newer device, wires can be guided in all directions and in all planes (sagittal, coronal, axial, and 360°). Correction of the wire direction using this jig is significantly easier and faster, a process which can take anywhere between 15min and an hour of surgical time for a beginner orthopaedic surgeon. The need for multiple repeated attempts to insert wires, resulting in a bone void and damage to the surrounding structures, is minimised or eliminated. Applications include a variety of surgical procedures of osteosynthesis and osteotomies. In conclusion, our device is easier to use as it is smaller in size and available in different sizes and angles. It not only avoids bone loss and fragmentation due to repetitive insertion of wires but also improves the accuracy of primary reference wire placement or revision of its direction.

Single access parallel wire technique for transcatheter aortic valve implantation.

Single access parallel wire technique for transcatheter aortic valve implantation.

An integral for self inductance of thin wires

Abstract I propose an elegant method of calculating the self inductance of a thin wire of arbitrary shape. The inductance is broken to into two parts - the inductance of a straight wire of the same length and cross section, and the remainder, the ‘curve inductance’ due to the shape of the axial curve. The curve inductance is finite and can be calculated from a double integral by subtracting the straight wire singularity inside the integrand. Unlike all other methods, this does not involve a small parameter, and can be applied to any curve knowing its arc length parameterization. We use the circular arc and helix as examples and find that the integral is fast and accurate. The limits of the approximation are investigated for touching parallel wires.

Study on Multi-Crack Damage Evolution and Fatigue Life of Corroded Steel Wires Inside In-Service Bridge Suspenders

The parallel steel wires used in arch bridge suspenders experience random corrosion damage on their surfaces during service. Corrosion damage, including micro-cracks, pitting, and a combination of both, leads to significant stress concentration under axial loading, which affects the performance of the steel wires. The change in the stress field caused by surface damage alters the stress intensity factor at the crack tip, and the presence of adjacent crack tips significantly amplifies the stress intensity factor, thereby accelerating crack propagation. The development of small surface damages in the steel wires is difficult to control and observe through experiments. By utilizing finite element methods for simulation, it is possible to intuitively analyze the crack propagation process, the trend of stress changes at the crack tip, and the interaction between damages. Numerical simulation results based on Paris’ law indicate that corrosion pits have a certain impact on the stress intensity factor at the crack tip. The propagation process of coplanar double cracks is highly sensitive to the initial crack size and the distance between adjacent crack tips. When the crack spacing is less than the crack depth, the stress intensity factor at the adjacent crack tips exhibits significant amplification. Based on this phenomenon, the coplanar double-crack system can be simplified to a complete single crack for analysis. By comparing the fatigue life of the double-crack system with that of the equivalent single crack, the effectiveness of the simplification rule has been validated.

Doubly Optimal Parallel Wire Cutting without Ancilla Qubits

A restriction in the quality and quantity of available qubits presents a substantial obstacle to the application of near-term and early fault-tolerant quantum computers in practical tasks. To confront this challenge, some techniques for effectively augmenting the system size through classical processing have been proposed; one promising approach is quantum circuit cutting. The main idea of quantum circuit cutting is to decompose an original circuit into smaller subcircuits and combine outputs from these subcircuits to recover the original output. Although this approach enables us to simulate larger quantum circuits beyond physically available circuits, it needs classical overheads quantified by two metrics: the sampling overhead in the number of measurements to reconstruct the original output, and the number of channels in the decomposition. Thus, it is crucial to devise a decomposition method that minimizes both of these metrics, thereby reducing the overall execution time. This paper studies the problem of decomposing the n-qubit identity channel, i.e., n-parallel wire cutting, into a set of local operations and classical communication; then we give an optimal wire-cutting method composed of channels based on mutually unbiased bases that achieves minimal overheads in both the sampling overhead and the number of channels, without ancilla qubits. This is in stark contrast to the existing method that achieves the optimal sampling overhead yet with ancilla qubits. Moreover, we derive a tight lower bound on the number of channels in parallel wire cutting without ancilla systems and show that only our method achieves this lower bound among the existing methods. Notably, our method shows an exponential improvement in the number of channels, compared to the aforementioned ancilla-assisted method that achieves optimal sampling overhead. Our work significantly alleviates the additional overheads for the wire-cutting method and may provide essential components for the early success of quantum computing. Published by the American Physical Society 2024

Dissimilar Resistance Welding of NiTi Microwires for High-Performance SMA Bundle Actuators

Shape memory alloys (SMAs) are becoming a more important factor in actuation technology. Due to their unique features, they have the potential to save weight and installation space as well as reduce energy consumption. The system integration of the generally small-diameter NiTi wires is an important cornerstone for the emerging technology. Crimping, a common method for the mechanical and electrical connection of SMA wires, has several drawbacks when it comes to miniaturization and high-force outputs. For high-force applications, for example, multiple SMA wires in parallel are needed to keep actuation frequencies high while scaling up the actuation force. To meet these challenges, the proposed study deals with the development of a resistance-welding process for manufacturing NiTi wire bundles. The wires are welded to a sheet metal substrate, resulting in promising functional properties and high joint strengths. The welding process benefits from low costs, easy-to-control parameters and good automation potential. A method for evaluating the resistance-welding process parameters is presented. With these parameters in place, a manufacturing process for bundled wire actuators is discussed and implemented. The welded joints are examined by peel tests, microscopy and fatigue experiments. The performance of the manufactured bundle actuators is demonstrated by comparison to a single wire with the same accumulated cross-sectional area.

Effect of Wrapping Force on the Effective Stiffness of Packed Parallel Wire Cables with Elastoplastic Contacts

Effect of Wrapping Force on the Effective Stiffness of Packed Parallel Wire Cables with Elastoplastic Contacts

A Subtractive Method to Chemically Pattern Liquid Metal for Stretchable Circuits

AbstractAdvancements in biomedical research have spurred the development of stretchable electronic devices. While soft insulators are readily available, soft conductors with metal‐like electrical conductivity are rare. Gallium and its alloys, being nontoxic and intrinsically stretchable, are potentially ideal solutions. However, current additive liquid metal (LM) patterning methods face limitations in achieving high‐throughput, high‐resolution, and high‐density LM wiring. Here, a subtractive LM patterning method is developed to meet all these requirements simultaneously. The innovative method involves parallel filling a single continuous microfluidic mesh network with LM that short‐circuits all the pins and pads of a circuit, followed by parallel cutting of the unwanted short‐circuited interconnections using hydrochloric acid (HCl) vapor. Cutting locations are pre‐defined by designing narrower intersecting channels, leveraging capillary force for precise filling and cutting. The process is characterized using a multidimensional parametric study with varying LM line widths and HCl concentrations, and in situ impedance measurements to assess insulation performance. To showcase its high‐throughput capabilities, a mock circuit is used to successfully generate complex LM interconnects that connected hundreds of electrical pads. Finally, a stretchable LM circuit with a micro‐LED array is fabricated to demonstrate the practical application of this technology for massively parallel wiring in stretchable electronics.

Optimized Chemical Bath Deposition for Low Cost, Scalable, and Environmentally Sustainable Synthesis of Star-Like ZnO Nanostructures.

This paper highlights an affordable and straightforward method called chemical bath deposition (CBD) for generating different morphologies of ZnO-based nanostructures. In particular, a specific protocol was found to drive the growth versus a high-yield in-plane symmetric six-arm nanostructure, named a nanostar (NS). Each arm of the star consists of a cluster of parallel wires, creating a subnanostructure with a huge surface-to-volume ratio. As-grown NSs present a mixed phase of ZnOHF and ZnO, which converts to ZnO under thermal annealing at 300 °C. The NSs have a highly exposed surface area (13.2702 m2·g-1) and exhibit an energy gap of 3.25 eV. A cradle-to-gate life cycle assessment (LCA) analysis has shown the high ecofriendly potential of this synthesis route and identified hotspots that need to be addressed to minimize the environmental impact of NS synthesis on an industrial scale.

A novel method for investigating the underwater explosion loads and bubble evolution

This paper presents an innovative experimental method for studying the evolution and energy output characteristics of underwater explosion bubbles. We independently constructed an experimental testing system for underwater electrical wire explosions (UEWE), in which electrodes connected to a metal wire serve as the load, and underwater explosions are initiated through instantaneous high-voltage discharge. By varying the diameter of the metal wire and configuring parallel wire arrays, we analyzed and discussed the explosion characteristic parameters and the current–voltage (I–V) signals under different conditions. The maximum bubble radius of the underwater metal wire explosion was compared with the corresponding equivalent explosive simulation results, and a numerical model for underwater metal wire explosion equivalent to explosive detonation was established. Subsequently, we discussed the characteristics of bubble generation and evolution under various conditions, clarifying the similarities and differences between wire explosions and explosive detonations. On this basis, we explored the propagation laws of shock waves and secondary pulsation waves (SPW) under different conditions. We also calculated and analyzed energy output characteristic parameters, such as shock wave energy and bubble energy. The results indicate that there are significant differences between copper wire and aluminum wire loads in UEWE. For copper wires with a diameter greater than 0.4 mm, the shock wave overpressure peak value significantly decreases, while for aluminum wires with a diameter greater than 0.5 mm, it slightly decreases. Both metals exhibit similar trends in parallel wire arrays, with the shock wave overpressure peak value initially increasing and then decreasing as the number of wires increases. Unlike underwater explosive detonations, the SPW peak value in UEWE may exceed that of the shock wave. For single wires, the SPW peak value of copper wires is generally higher than that of aluminum wires, but in wire arrays, the trend is reversed. The multi-wire parallel connection can improve the energy conversion efficiency of the shock waves. However, for bubble energy, under all conditions, a single aluminum wire with a diameter of 0.5 mm produced the maximum bubble energy, reaching 1023.1 J. These findings provide new insights into the energy features of UEWE.

Estimation of heat source, specific heat, and thermal conductivity of insulation materials using modified conjugate gradient method

The use of insulation materials is crucial for minimizing thermal losses in various industries like automotive, building, solar, and aerospace. Plexiglass and Expanded Polystyrene (EPS) foam are popular choices due to their effective temperature regulation, lightweight nature, and cost-effectiveness. Accurate measurement of their thermal properties is vital for achieving conservation goals. While the parallel hot wire technique provides valuable insights, accurately determining heat source strength (HW) poses a challenge, impacting measurement accuracy. To address this, the modified Conjugate Gradient Method (CGM) is employed for simultaneous estimation of thermal conductivity (λ), specific heat (c) and HW of Plexiglass and EPS foam. The direct problem result has been validated with published experimental work that shows deviations less than 2 %. The study investigates the impact of sensor positioning relative to the hot-wire (rm) and introduces artificial Gaussian error with standard deviations (θ) of 0.01 °C, 0.02 °C and 0.1 °C. At θ = 0.1 °C the percentage relative errors in the estimation of λ, c and HW with rm = 5 mm for Plexiglass are 5 %, 1.442 %, and 4.651 % respectively. For EPS foam the corresponding errors are 2.44 %, 1.26 %, and 1.74 %. The modified CGM emerges as a reliable algorithm for the measurement of thermal properties of insulation materials.

Comparative study on upward flame spread interactions and heat transfer over two parallel wires with various spacing distances in open space and vertical channel

Most previous work focused on the flame spread interactions and heat transfer over two parallel wires in open space, but few studies considered the vertical channel effects. Experiments were carried out to investigate the influence of vertical channel on the flame spread interactions and heat transfer over two parallel wires. Two types of polyethylene-insulated copper wires were used with spacing distance ranging from 0 mm to 52 mm. Whether for open space or vertical channel, four typical regimes of upward flame interactions are observed as a function of spacing distance, but the range of these regimes is affected by the vertical channel. For open space and vertical channel, the flame width, flame length and flame spread rate rise first and then drop, but these parameters for vertical channel are larger than that for open space due to the enhanced induced flow and the heat transfer. A heat transfer model is established for upward flame spread over two parallel wires taking the effects of spacing distance and vertical channel, in which the radiation from flame is considered, as well as the difference between the solid-phase and gas-phase heating lengths. The flame heat feedback is the dominant mechanism for upward flame spread over two parallel wires, and it for vertical channel is larger than that for open space.

The use of fully threaded headless cannulated screws for femoral neck fracture fixation in small-breed dogs show promise in cadaveric study.

To biomechanically evaluate the stability of internal fixation methods for femoral neck fractures in small-breed dogs. Furthermore, the possibility of replacing the headed screw with fully threaded headless cannulated screws in the fixation method was assessed. The study was conducted from December 12, 2023, to February 7, 2024. A total of 18 femurs from 9 canine cadavers were used in this study. After a simple neck fracture was created, in group A (n = 6), the fracture was stabilized with three 1.1-mm parallel Kirschner wires (K-wires). In group B (n = 6), a 3.0-mm partially threaded cannulated screw and an antirotation pin were used. In group C (n = 6), a 2.5-mm fully threaded headless cannulated screw and an antirotation pin were used. A mechanical test was conducted to apply a single axial compressive load to the femoral head. 9 adult small-breed dogs weighing 3.6 to 8.3 kg (mean ± SD; 5.9 ± 1.6). The mean maximum failure load was highest in group C (495 ± 81 N), followed by group B (454 ± 50.4 N), and then group A (222 ± 21.6 N). Significant differences in maximum failure load were observed between groups A and B as well as groups A and C but not between groups B and C. The use of fully threaded headless cannulated screws presents a promising method for internal fixation of canine femoral neck fractures. To demonstrate the potential stability and reliability of fully threaded headless cannulated screws.

Fatigue life prediction of corroded hangers with parallel steel wire in a network arch bridge under vehicle-bridge interaction based on a novel noniterative simplified method

Fatigue damage is a main concern during the life-cycle maintenance of bridges with corroded hangers under vehicle-bridge interaction (VBI). In this study, a novel noniterative simplified method for VBI is proposed to analyze the responses of hangers in a network arch bridge, considering the effects of vehicle types, driving lanes, and road surface roughness. Furthermore, the fatigue life of corroded hangers is investigated, considering the actual traffic flow and uneven distribution of stress in the hanger’s cross-section. The results show that longitudinal and transverse bending moments of the hanger significantly affect the stress of steel wires in one hanger but have limited influence on stress amplitudes. The fatigue lives of steel wires are considerably reduced when subjected to both uniform and pitting corrosion. The fatigue life of steel wires is reduced under deteriorating road surface conditions. Moreover, as the fatigue life of steel wires in the hangers declines, the variations in fatigue life among individual steel wires within a single hanger gradually decrease. Consequently, this trend leads to a heightened likelihood of continuous wire breakage.