Three-dimensional Probe Research Articles

CardiacField: computational echocardiography for automated heart function estimation using two-dimensional echocardiography probes

Abstract Aims Accurate heart function estimation is vital for detecting and monitoring cardiovascular diseases. While two-dimensional echocardiography (2DE) is widely accessible and used, it requires specialized training, is prone to inter-observer variability, and lacks comprehensive three-dimensional (3D) information. We introduce CardiacField, a computational echocardiography system using a 2DE probe for precise, automated left ventricular (LV) and right ventricular (RV) ejection fraction (EF) estimations, which is especially easy to use for non-cardiovascular healthcare practitioners. We assess the system’s usability among novice users and evaluate its performance against expert interpretations and advanced deep learning (DL) tools. Methods and results We developed an implicit neural representation network to reconstruct a 3D cardiac volume from sequential multi-view 2DE images, followed by automatic segmentation of LV and RV areas to calculate volume sizes and EF values. Our study involved 127 patients to assess EF estimation accuracy against expert readings and two-dimensional (2D) video-based DL models. A subset of 56 patients was utilized to evaluate image quality and 3D accuracy and another 50 to test usability by novice users and across various ultrasound machines. CardiacField generated a 3D heart from 2D echocardiograms with <2 min processing time. The LVEF predicted by our method had a mean absolute error (MAE) of 2.48%, while the RVEF had an MAE of 2.65%. Conclusion Employing a straightforward apical ring scan with a cost-effective 2DE probe, our method achieves a level of EF accuracy for assessing LV and RV function that is comparable to that of three-dimensional echocardiography probes.

New high-field side magnetic probe array system for three-dimensional magnetic fluctuation measurements on EAST

To better study the magnetic fluctuations in the high-field side of EAST tokamak, a new high-field side magnetic probe array (HFS-MPA) has been developed on EAST recently. The HFS-MPA consists of 12 identical three-dimensional (3D) magnetic probes, which are mounted on the HFS wall with carefully designed arrangement. The HFS-MPA magnetic probes bring additional toroidal magnetic fluctuation measurements compared with the HFS regular magnetic probes which can only provide poloidal and radial magnetic fluctuation measurements. The upper limits of frequency and toroidal mode number (n) measurements of the magnetic fluctuations have been improved by comparing HFS-MPA with the HFS regular magnetic probes, i.e., 650 kHz vs 100 kHz and n = 23 vs n = 1. In developing the HFS-MPA diagnostic system, many practical challenges have been overcome and many special designs have been developed. These will be mentioned in the main subsystem description of the HFS-MPA diagnostic in this paper, which might be useful for developing new magnetic probe diagnostics in the future on EAST or other magnetically confined fusion devices. The calibration of the effective area and frequency response of the HFS-MPA is also described. The preliminary application in studying the frequency and propagation characteristics of the magnetic fluctuations with HFS-MPA compared with EAST regular magnetic probes shows that the HFS-MPA is well developed for plasma physics studies.

Design of Three-Dimensional Magnetic Probe System for Space Plasma Environment Research Facility (SPERF).

A three-dimensional magnetic probe system has been designed and implemented at the Space Plasma Environment Research Facility (SPERF). This system has been developed to measure the magnetic field with high spatial and temporal resolution, enabling studies of fundamental processes in space physics, such as magnetic reconnection at the Earth's magnetopause, on the basis of SPERF. The system utilizes inductive components as sensors, arranged in an array and soldered onto a printed circuit board (PCB), achieving a spatial resolution of 2.5 mm. The system's electrical parameters have been measured, and its amplitude-frequency response characteristics have been simulated. The system has demonstrated good performance with response capabilities below 50 kHz. The experimental setup and results are discussed, highlighting the system's effectiveness in accurately measuring weak magnetic signals and its suitability for magnetic reconnection experiments.

Analysis of the effect of probe structure on sampling accuracy in supersonic airflow

The accuracy of the sampling of the gas components has a significant impact on the measurement of various performance parameters in the combustion chamber of an aero-engine. This paper examines the accuracy of a six-point gas sampling probe when used in supersonic airflow. A numerical simulation method of component transport and fluid-solid coupling is employed to construct a three-dimensional probe multi-component gas flow characteristic solution model. Three kinds of probes with 28°, 30° and 32° angles and structure-modified conical probes were established, and the influence law of probe structure on gas sampling accuracy was analyzed. The results of the study demonstrate that the 28° and structurally modified conical probes yield a more effective improvement in sampling accuracy in comparison to the original 30° structure. The test data of the test bench are in good agreement with the simulation results, thereby demonstrating the reliability and accuracy of the sampling probe following structural modification.

Analysis of the Effect of Sampling Probe Geometry on Measurement Accuracy in Supersonic Gas Flow

The accuracy of sampling of gas components has a significant impact on the measurement of various performance parameters in the combustion chamber of an aero-engine. In order to investigate the effect of the probe geometry of a six-point gas sampling probe on sampling accuracy in supersonic gas flow, a three-dimensional probe gas flow characteristic solution model is established through numerical simulation methods of components of transport and fluid–solid coupling. Probes with three angles of 28°, 30°, and 32° and an optimized conical probe are constructed. The sampling accuracy of the probes with different geometries is compared and evaluated by the deviation of the component volume fraction before and after sampling and the resulting combustion efficiency error. This paper presents a set of calculation methods for solving the relative deviation of volume fraction by an iterative method based on the ideal gas law and the Redlich–Kwong equation (R-K equation). The method is designed to solve the exact component volume fraction problem in the simulation calculation. The study results demonstrate that the 28° and optimized conical probes improve sampling accuracy more effectively than the original 30° structure. The deviation of the volume fractions of the two structures is less than 1.7%, and the combustion efficiency error is less than 0.09%. The developed iterative calculation method can significantly reduce the theoretical calculation error to less than 0.06%. The experimental data of the test bench are in good agreement with the simulation results, thereby demonstrating the reliability and accuracy of the sampling probe following structural optimization.

Promising Molecular Architectures for Two-Photon Probes in the Diagnosis of α-Synuclein Aggregates.

The abnormal deposition of protein in the brain is the central factor in neurodegenerative disorders (NDs). These detrimental aggregates, stemming from the misfolding and subsequent irregular aggregation of α-synuclein protein, are primarily accountable for conditions such as Parkinson's disease, Alzheimer's disease, and dementia. Two-photon-excited (TPE) probes are a promising tool for the early-stage diagnosis of these pathologies as they provide accurate spatial resolution, minimal intrusion, and the ability for prolonged observation. To identify compounds with the potential to function as diagnostic probes using two-photon techniques, we explore three distinct categories of compounds: Hydroxyl azobenzene (AZO-OH); Dicyano-vinyl bithiophene (DCVBT); and Tetra-amino phthalocyanine (PcZnNH2). The molecules were structurally and optically characterized using a multi-technique approach via UV-vis absorption, Raman spectroscopy, three-dimensional fluorescence mapping (PLE), time-resolved photoluminescence (TRPL), and pump and probe measurements. Furthermore, quantum chemical and molecular docking calculations were performed to provide insights into the photophysical properties of the compounds as well as to assess their affinity with the α-synuclein protein. This innovative approach seeks to enhance the accuracy of in vivo probing, contributing to early Parkinson's disease (PD) detection and ultimately allowing for targeted intervention strategies.

Coherent manipulation of three-dimensional probe absorption spectrum in a strained GaAs-AlGaAs-InAs semiconductor quantum dot

Coherent manipulation of three-dimensional probe absorption spectrum in a strained GaAs-AlGaAs-InAs semiconductor quantum dot

High-throughput first-principles study on the effect of Ni segregation on the formation of Cr-depleted zone and corrosion resistance of S32205 duplex stainless steels

Recent studies have found that in the absence of Cr carbide precipitation, co-segregation of Cr and other elements at the interface between α-Fe and γ-Fe can also lead to the formation of Cr-depleted zones, leading to intergranular corrosion. The study employed three-dimensional atomic probes, focused ion beams, and high-throughput first-principles calculation techniques to investigate the impact of Ni atoms on the α-Fe/γ-Fe interface of UNS S32205 duplex stainless steels. The goal was to analyze the formation of Cr-depleted zones and interface corrosion resistance. The results indicate that both Ni and Cr atoms are segregated at the interface between α-Fe and γ-Fe phases; The strong interaction between Ni and Cr atoms hinders Cr segregation at the interface and slows down the formation of Cr-depleted zones; co-segregation of Ni and Cr can improve the stability of the α-Fe/γ-Fe phase interface, reduce the generation of microcracks, and reduce the stability of Cl atom adsorption in the cracks. This establishes the theoretical basis for further suppressing the formation of Cr-depleted zones and preventing intergranular corrosion.

Experimental reconstruction of the local flow field in a Wells turbine using a three-dimensional pressure probe

Among the various solutions suggested for wave energy harvesting, the ones based on the oscillating water column (OWC) principle are considered as the most promising, due to their constructive simplicity and reliability. These systems convert sea wave energy into pneumatic energy in the form of a bi-directional airflow that can conveniently turned into mechanical energy by a Wells turbine. Since their introduction, Wells turbines have been studied extensively in order to characterize their performance. Most of the experimental studies have focused on global machine performance analyses, while the studies focusing on local performance analyses are limited. This work presents a detailed experimental investigation of a small-scale Wells turbine coupled to an OWC simulator. The turbine aerodynamic characteristic has been identified with global measurements, while a miniaturized aerodynamic probe has been used to evaluate local performance, by reconstructing the three-dimensional flow field upstream and downstream of the turbine during a complete regular wave period. Local analyses aid to explain global turbine performance, highlighting the main differences between inflow and outflow phases. Moreover, they allow to describe the variation in loading along the blade radius, and to evaluate the blade design law, which justifies the limited Wells turbine aerodynamic performance.

Experimental investigation of a near-field focusing performance of the IP-Dip polymer based 2D and 3D Fresnel zone plate geometries fabricated using 3D laser lithography coated with hyperbolic dispersion surface layered metamaterial

Abstract Herein we investigate the character of the near-field emission of a two- (2D) and novel three-dimensional (3D) probe geometries fabricated using 3D direct laser writing lithography. Near-field scans in x–y and y–z planes were measured both before and after the deposition of hyperbolic dispersion metamaterial (HMM) to further verify the directional propagation of the high wave-vector components present in the vicinity of the structures. Additional computational and theoretical characterization forewent the actual experimental measurements, showing a promising performance, particularly for the 3D Fresnel zone plate (FZP). Overall, the experimental data documents a subwavelength resolution with a significant signal enhancement in the focal spot of the 3D FZP and highly subwavelength depth of focus.

A comprehensive study on the thermodynamics of the Al13Fe4 solid solution in the Al-Fe-Mn ternary system

This paper presents investigations on the thermodynamic stability of the Al13Fe4 solid solution in the Al-Fe-Mn ternary system as well as its crystal chemistry characterisation. In order to carry out this study, the isobaric heat capacity of the solution was measured at high temperature using a high precision three-dimensional probe. The heat capacity of the Al13Fe4 binary compound measured in this study between 600 K and 1223 K is CP(T) = 23.97 + 8.18.10−2T − 7.63.105T2. This value is significantly different from other measurements reported in the literature. We show in this paper that our measurements are more accurate than those available in the literature thanks to the use of a more precise sensor (3D-Cp sensor versus planar DSC sensor). As a result, our measurements are more thermodynamically consistent with the enthalpy of formation values of the Al13Fe4 compound available in the literature, as well as with our own enthalpy of formation measurement performed independently of the heat capacity measurement presented in this paper. Measurements of the enthalpy of formation of the solid solution were also performed by in-situ synthesis in a DSC. These new measurements were complemented by DFT calculations of the enthalpy of formation at 0 K of the solid solution. Our calculations and measurements show that the substitution of Fe by Mn is responsible for a large increase in the solid solution enthalpy of formation. These new experimental and calculated data were used to develop a thermodynamic model of the solution. Finally, we utilized our model to calculate the Fe site occupation factors (sof) of the solid solution structure over its entire chemical composition range (simulating the complete substitution of all Fe atoms with Mn) as a function of temperature. The chemical ordering of the solid solution was thus quantified, revealing its ideal nature near its melting temperature. These results allowed the development of a new SL-model for the solution, both simpler and more reliable than those used in the literature.

A model construction and measurement method for tooth surface deviation of spiral bevel gear based on a one-dimensional probe

The accurate measurement of tooth surface deviation is an important prerequisite for the quality monitoring of high-precision spiral bevel gears. A measurement method for tooth surface deviation of spiral bevel gears is proposed based on a one-dimensional probe, which can accurately measure and evaluate tooth flank. According to the forming principle of the spiral bevel gear tooth surface, the theoretical surface is constructed as the measurement reference flank. A series of measures and methods are adopted to ensure the accuracy and correctness of one-dimensional probe measurement. These effective methods include the construction of a precise positioning model of the gear blank and its surface, the measurement planning of reduction dimension which the gear needs to rotate once the normal angle after each point is measured, and the compensation for the increasing dimension of the one-dimensional probe. In addition, minimization of the normal deviation of the tooth flank is achieved by using the optimum matching technique of the theoretical and the actual surfaces. The deviation degree of the actual surface relative to the theoretical surface can be accurately calculated and evaluated by establishing a deviation model, which ensures the correctness of the evaluation result of the deviation. Finally, the test of tooth surface deviation is carried out on a JD45+ gear measuring center (GMC) using a one-dimensional probe and a Gleason 650GMS GMC using a three-dimensional probe. The measurement results show that the evaluation results of the one-dimensional probe are in good agreement with those of the three-dimensional probe. The proposed theory and method not only expand the measurement range of the GMC using a one-dimensional probe, but also have certain reference significance for the precision measurement of other complex surfaces.

Development of a removable three-dimensional magnetic probe system for measuring field null on the NanChang Spherical Tokamak.

The field null configuration of a poloidal magnetic field is one of the critical conditions for achieving Ohmic breakdown during the initial discharge of a new tokamak. The issue of the Ohmic breakdown on the NanChang Spherical Tokamak (NCST) is still not solved satisfactorily although plasma currents of about 2kA were found. Hence, a removable three-dimensional magnetic probe (RTMP) system consisting of 25 magnetic probes was designed, calibrated, and constructed on the NCST to evaluate the field null inside a vacuum vessel. After repeated tests, the RTMP system exhibited outstanding performance in terms of accuracy and stability with errors of about 1%. Meanwhile, the RTMP system successfully measured the toroidal field (TF) coil ripples at the magnetic axis. During experiments, the stray field arising from the TF coil implied a strong link between the flexible connection of the TF coil and the Ohmic breakdown on the NCST. After the field null was effectively modified by using a new flexible connection of the TF coil and controlling the induced current in the poloidal field coil, the NCST tokamak reproducibly obtained 20kA plasma current with the limiter configuration during the plasma current flat-top phase.

A three-dimensional electrode array probe designed for visualising complex and dynamically changing internal pipeline corrosion

This short communication describes a corrosion probe design concept based on a three-dimensional electrochemically integrated electrode array. A representative probe was made for probing complex localised corrosion inside a liquid-containing pipe. Results demonstrate that the probe has sufficient temporal and spatial resolutions required for in-situ monitoring of atmospheric corrosion, channelling corrosion and flow-affected corrosion occurring simultaneously inside the pipe, and for investigating the effects of corrosion influencing factors including differential aeration, liquid flowing, pH and inhibitors. This work suggests that the three-dimensional electrode array probe is a promising tool for probing multi-phase and multi-mechanism localised corrosion in complex industrial environment.

A High-Precision Three-Dimensional Probe Array Temperature Sensor

To meet the need for micro-volume devices for high-precision measurement of temperature, Cu-Constantan (CuNi45) thin films with a novel array structure of thermo-electrodes were designed and fabricated. The thermo-electrodes on the probe-type substrate were deposited by magnetron sputtering technology and the profiling mask was prepared by 3D printing technology. The comprehensive performance of the temperature sensor was improved by systematic optimization of the heat treatment process and accuracy correction algorithm. Results showed that the sensor can measure with an accuracy of up to ±0.19%FS from −60 °C to 200 °C. The three-dimensional probe array temperature sensor shows great advantages in sensitivity, reliability resolution, stability, and measurement accuracy.

Numerical calculation of near-field in vicinity of three-dimensional nano-optical probes using boundary element method

The diffraction limit is one of the main obstacles in the development of microscopes to analyze the morphology and structure of materials. The main idea of near field scanning optical microscopy (NSOM) is to overcome the diffraction limit using sub-wavelength apertures. In this work, the near-field is simulated in the vicinity of three-dimensional nano-optical apertureless probes. For this purpose, the Helmholtz equation is solved using the boundary element method (BEM). The effects of different parameters on the near field generated in the vicinity of the optical probe are studied. These parameters consist of the length and radius of the probe, the size of the aperture, the angle of the tapered tip, and the geometry of the probe tip. The main advantages of the proposed method are the high accuracy, the very short calculation time, and the ability to calculate the near field inside and outside the optical probe without any approximation.

A Model for Characteristic X-Ray Emission in Electron Probe Microanalysis Based on the (Filtered) Spherical Harmonic () Method for Electron Transport

Classical$k$-ratio models, for example, ZAF and$\phi ( \rho z)$, used in electron probe microanalysis (EPMA) assume a homogeneous or multilayered material structure, which essentially limits the spatial resolution of EPMA to the size of the interaction volume where characteristic X-rays are produced. We present a new model for characteristic X-ray emission that avoids assumptions on the material structure to not restrict the resolution of EPMAa priori. Our model bases on the spherical harmonic ($P_{\rm N}$) approximation of the Boltzmann equation for electron transport in continuous slowing down approximation.$P_{\rm N}$models have a simple structure, are hierarchical in accuracy and well-suited for efficient adjoint-based gradient computation, which makes our model a promising alternative to classical models in terms of improving the resolution of EPMA in the future. We present results of various test cases including a comparison of the$P_{\rm N}$model to a minimum entropy moment model as well as Monte-Carlo (MC) trajectory sampling, a comparison of$P_{\rm N}$-based$k$-ratios to$k$-ratios obtained with MC, a comparison with experimental data of electron backscattering yields as well as a comparison of$P_{\rm N}$and MC based on characteristic X-ray generation in a three-dimensional material probe with fine structures.

Synthesis of a Lanthanide Metal-Organic Framework and Its Fluorescent Detection for Phosphate Group-Based Molecules Such as Adenosine Triphosphate.

Adenosine triphosphate (ATP) is an important kind of metabolized biological molecule that is formed in organisms, especially in mitochondria, is used universally as energy, and is one of the most significant multifunctional biological molecules. Metal-organic frameworks (MOFs) have been widely used in many applications such as gas storage and separation, drug delivery, heterogeneous catalysis, chemical sensors, etc. Remarkably, lanthanide MOFs (Ln-MOFs), which display large pores, multiple dimensions, and unique lanthanide luminescence properties, are widely used as chemical sensors. A novel three-dimensional probe, Eu2(sbdc)3(H2O)3 (Eu-sbdc), was successfully self-assembled with Eu(NO3)3·6H2O and 5,5-dioxo-5H-dibenzo[b,d]thiophene-3,7-dicarboxylic acid (H2sbdc). The Ln-MOF Eu-sbdc can quickly and effectively optically detect ATP via a luminescent quenching mechanism. The Ksv value of Eu-sbdc is 1.02 × 104 M-1, and the lower detection limit of Eu-sbdc for ATP is 20 μM, which is more sensitive to ATP. Its mechanism of monitoring ATP might be a dynamic or static quenching process. Eu-sbdc could effectively and quickly recognize ATP with high sensitivity.

Fabrication of a three-dimensional (3D) SERS fiber probe and application of in situ detection.

Surface-enhanced Raman scattering (SERS) fiber probes are useful for remote and online detection of harmful molecules using the SERS effect. In this study, a 3-dimensional (3D) SERS optical fiber probe is proposed. The formation of the 3D optical fiber probe mainly included three steps: construction of monolayer polystyrene (PS) spheres as a mask on the end face of the fiber, reactive ion etching (RIE) for PS spheres and fibers, and metal sputtering deposition. Compared with flat surface fiber probes, these 3D SERS fiber probes are composed of ordered nanocolumn arrays, which have the advantages of a simple manufacturing process, low cost, high sensitivity, and good stability. The structures of the 3D SERS fiber probe can be well controlled by changing the size of the PS sphere and etching time. The formation of the nanocolumn was studied using time evolution experiments. The obtained fiber SERS probe has good stability and high sensitivity for the in situ detection of 4-aminothiophenol (4-ATP) in solution. Therefore, these 3D SERS fiber probes have potential applications in harmful molecules for real-time detection.

Partial Discharge Detection Based on Optimization of Optical Probe and Sagnac Interference

Partial discharge (PD) measurement is necessary for insulation diagnosis and usually a required item of the maintenance procedure for most high voltage equipment assets. optical fiber sensor (OFS) provides an innovative and nondestructive approach to convert PD-induced acoustic signal into optical parameter, but the optical probe is challengeable since it is the key component to pick up the extremely weak PD-induced acoustic signal. A universal three-dimensional skeleton-type fiber probe is designed. To optimize the specific parameters of the optical probe, the multi-parameter sensitivity model of tiny skeleton-type optical fiber probe is proposed and established, involving in the material, physical height, radius, and the sensing fiber length. A skeleton-type probe with a wingding length of 60 m, the skeleton height of 12 mm, and peek material is designed for PD ultrasonic sensing. Theoretical modeling, mathematical simulation, sensitivity calibration, and comparative PD tests with regard to the sensing probe and the corresponding specific optical PD measurement system. PD results show that the average detection amplitude of the developed optical fiber sensor is 1.27 times that of commercial piezoelectric transducer (PZT). The flexible installation and the enhanced sensitivity make the Sagnac ultrasonic sensing system an excellent approach to detect and locate weak PD signals inside the power apparatus.