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3D printing stereolithography (SL) technique were successfully applied in the preparation of <001>-textured 0.71Pb(Mg 1/3 Nb 2/3)O 3 -0.29PbTiO 3 (PMN-29PT) ceramics in this work. The as-sintered textured ceramics show obvious grain orientation control effects, and the relative density reaches 93% of the theoretical density. The obtained ceramics demonstrate typical dielectric/ferroelectric/piezoelectric properties, enabling the device applications. The ultrasonic transducer with the center frequency of 6.7 MHz and the −6 dB bandwidth of 25% are designed and prepared based on the obtained textured ceramic. This work signifies the great potential of 3D printing SL technology on the fabrication of piezoelectric ceramic elements for advanced applications. [ABSTRACT FROM AUTHOR]

Design optimization of multilayer piezoelectric transducers is intended for efficient and practical usage of wideband transducers for fault diagnosis, biomedical, and underwater applications through adjusting layer thicknesses and volume fraction of piezoelectric material in each layer. In this context, we propose a parallel differential evolution (PDE) algorithm to mitigate the complexities of multivariate optimization as well as the computation time to achieve an optimized wideband transducer for the particular application. For lead magnesium niobate-lead titanate (PMN PT)- and PZT5h-based piezoelectric materials, the fitness function is formulated based on uniformity of mechanical pressure at the first three harmonics to achieve wide bandwidth in the required functional frequency range. It is carried out using a one-dimensional model (ODM), while input layer thicknesses and volume fractions of active material are evaluated using PDE. The simulation is performed on a parallel computing platform utilizing three different host machines to reduce computational time. Results of the proposed methodology for PDE are statistically represented in the form of minimum, maximum, mean, and standard deviation of fitness value, while graphically represented in terms of speedup and time. It can be observed that the execution time for parallel DE decreases with the increasing number of cores. [ABSTRACT FROM AUTHOR]

Vestibular evoked myogenic potentials (VEMPs) are a tool to assess otolith function and a component of sensor specific vestibular diagnostics. The aim of the present study was to measure VEMP trough bone conducted (BC) stimulation using the B250 prototype and to report amplitudes, latencies and threshold levels for patients before resection of a sporadic unilateral vestibular schwannoma (VS) in order to assess function regarding to the reported nerve of origin. Twenty-seven participants (9 male/18 female) with a mean age of 55.9 years (SD: 10.8) were included for the analysis. In the side contralateral to the tumor, in 24 (89%) of the patients cVEMP could be measured, while oVEMP were recordable in 20 patients (74%). For patients with inferior vestibular nerve of origin (n = 11), cVEMP amplitudes of the affected side were significantly lower as compared to the non-affected side, while the force threshold level was increased. No statistically significant differences were observed for neither, oVEMP amplitudes nor threshold levels in the group with superior vestibular nerve of origin (n = 7). Across groups, p13 latency was significantly increased in the affected ear while all other VEMP latencies were not different between the ears. The B250 transducer was applicable to all participants of the clinical cohort. The sample size, however, was too low for a reliable statistical analysis and only allowed for exploratory analysis. [ABSTRACT FROM AUTHOR]

This paper presents an experimental approach to maximizing the voltage generated by NaxCoO2 and improving the overall efficiency of the p-type thermoelectric leg by doping with Na up to x = 0.88. Two samples with different geometries were tested, each measured with and without an additional magnetic field applied in the direction of the temperature gradient. The properties of sodium cobaltite in response to hydration were explored, at temperatures between 300   a n d   380 K. Water injection boosted the current and power up to 75–100 µW at a temperature of 350–360 K. This power boost can be attributed to an electron-ion fluid flow pattern maintained by the longitudinal thermomagnetic effect and by water molecules forming hydrogen bonds with oxygen atoms in the CoO2 layers, inside the material. An electronic circuit was designed to boost the voltage to the desired level, for three or more sodium cobaltite samples mounted in parallel, and to store the energy in a supercapacitor. The output voltage and resistivity change of sodium cobaltite samples can be readily used as a humidity and temperature-sensing element in a transducer when paired with an appropriate electronic conditioning scheme. [ABSTRACT FROM AUTHOR]

Abstract Vestibular evoked myogenic potentials (VEMPs) are a tool to assess otolith function and a component of sensor specific vestibular diagnostics. The aim of the present study was to measure VEMP trough bone conducted (BC) stimulation using the B250 prototype and to report amplitudes, latencies and threshold levels for patients before resection of a sporadic unilateral vestibular schwannoma (VS) in order to assess function regarding to the reported nerve of origin. Twenty-seven participants (9 male/18 female) with a mean age of 55.9 years (SD: 10.8) were included for the analysis. In the side contralateral to the tumor, in 24 (89%) of the patients cVEMP could be measured, while oVEMP were recordable in 20 patients (74%). For patients with inferior vestibular nerve of origin (n = 11), cVEMP amplitudes of the affected side were significantly lower as compared to the non-affected side, while the force threshold level was increased. No statistically significant differences were observed for neither, oVEMP amplitudes nor threshold levels in the group with superior vestibular nerve of origin (n = 7). Across groups, p13 latency was significantly increased in the affected ear while all other VEMP latencies were not different between the ears. The B250 transducer was applicable to all participants of the clinical cohort. The sample size, however, was too low for a reliable statistical analysis and only allowed for exploratory analysis.

Highlights Magnetic elastomer composites are extending the field of soft robotics by integrating the flexibility of elastomers with the versatile performance of magnetic materials. In this work, a series of magnetic elastomers (BaCoxTixFe12–2xO19/PDMS) with tunable magnetic response have been successfully synthesized. In this composite, the magnetic component consists of Co‐Ti co‐doped barium hexaferrite (BaCoxTixFe12–2xO19, BCTF) nano powders, and the matrix is made of polydimethylsiloxane (PDMS). The coercivity (Hc) of BCTF can be reduced from 3950 Oe to 70 Oe, which bestow on the magnetic elastomer different magnetic response behavior. These magnetic elastomer composites obtained by blending have low Young's modulus, approximately 1.5 MPa. Furthermore, when applying the same external magnetic field, BaCo1.2Ti1.2Fe9.6O19/PDMS the magnetic deformation Angle can be as high as 60°. These magnetic elastomers exhibit different magnetic‐induced deformation owing to the adjustable permeability of the magnetic nanoparticles. This research significantly advances the design of applications with specific magnetic characteristics, such as sensors and transducers, thus opening new horizons for innovation in soft robotics and related fields. All elastomer composite exhibit a low modulus of approximately 1.5 MPa. These composites exhibit different magnetic response behaviors. This research provides a solution for the innovation of transducers. [ABSTRACT FROM AUTHOR]

Accurate measurement of the pretightening stress for bolts has great significance for improving the assembly quality and safety, especially in severe environments. In this study, AlN thin film transducers were deposited on GH4169 nickel base alloy bolts using the RF magnetron sputtering, enabling a systematic investigation into the correlation between structures and the intensity of ultrasonic echo signals. Employing the finite element method resulted in consistency with the experimental data, enabling further exploration of the enhancement mechanism. With the increasing thickness of both the piezoelectric layer and the electrode layer, the intensity of the ultrasonic echo signals saw a great enhancement. The maximum-intensity observed increase is 14.7 times greater than that of the thinnest layers. Specifically, the thicker piezoelectric layer improves its mechanical displacement, while the increased thickness of the electrode layer contributes to better densification. An electrode diameter of nearly 4 mm is optimal for an AlN thin film transducer of M8 bolts. For pretightening the stress measurement, the sample with a strong and stable echo signal shows a low measurement error of pretightening below ±2.50%. [ABSTRACT FROM AUTHOR]

Medical ultrasound has emerged as an indispensable tool within interventional pulmonology, revolutionizing diagnostic and procedural practices through its non-invasive nature and real-time visualization capabilities. By harnessing the principles of sound waves and employing a variety of transducer types, ultrasound facilitates enhanced accuracy and safety in procedures such as transthoracic needle aspiration and pleural effusion drainage, consequently leading to improved patient outcomes. Understanding the fundamentals of ultrasound physics is paramount for clinicians, as it forms the basis for interpreting imaging results and optimizing interventions. Thoracic ultrasound plays a pivotal role in diagnosing conditions like pleural effusions and pneumothorax, while also optimizing procedures such as thoracentesis and biopsy by providing precise guidance. Advanced ultrasound techniques, including endobronchial ultrasound, has transformed the evaluation and biopsy of lymph nodes, bolstered by innovative features like elastography, which contribute to increased procedural efficacy and patient safety. Peripheral ultrasound techniques, notably radial endobronchial ultrasound (rEBUS), have become essential for assessing pulmonary nodules and evaluating airway structures, offering clinicians valuable insights into disease localization and severity. Neck ultrasound serves as a crucial tool in guiding supraclavicular lymph node biopsy and percutaneous dilatational tracheostomy procedures, ensuring safe placement and minimizing associated complications. Ultrasound technology is suited for further advancement through the integration of artificial intelligence, miniaturization, and the development of portable devices. These advancements hold the promise of not only improving diagnostic accuracy but also enhancing the accessibility of ultrasound imaging in diverse healthcare settings, ultimately expanding its utility and impact on patient care. Additionally, the integration of enhanced techniques such as contrast-enhanced ultrasound and 3D imaging is anticipated to revolutionize personalized medicine by providing clinicians with a more comprehensive understanding of anatomical structures and pathological processes. The transformative potential of medical ultrasound in interventional pulmonology extends beyond mere technological advancements; it represents a paradigm shift in healthcare delivery, empowering clinicians with unprecedented capabilities to diagnose and treat pulmonary conditions with precision and efficacy. By leveraging the latest innovations in ultrasound technology, clinicians can navigate complex anatomical structures with confidence, leading to more informed decision-making and ultimately improving patient outcomes. Moreover, the portability and versatility of modern ultrasound devices enable their deployment in various clinical settings, from traditional hospital environments to remote or resource-limited areas, thereby bridging gaps in healthcare access and equity. [ABSTRACT FROM AUTHOR]

AbstractThe agricultural tractor serves as a pivotal power source on the farm. However, the optimal utilization of tractor power has often been hindered by factors such as non-matching implement sizes and suboptimal operating skills, leading to underutilization of power potential across diverse field conditions. In response, a study was initiated to formulate a cost-effective embedded system capable of on-the-go digital display and recording of various field performance parameters, ensuring precision in geographical location tracking. An embedded system, seamlessly incorporating a global positioning system (GPS), was successfully integrated onto an agricultural tractor to facilitate the mapping of tractor-implement performance. The developed embedded system employed Hall effect sensors for measuring theoretical speeds at both tractor rear drive wheels, as well as the actual speed at the tractor front wheel. Additionally, forces at the tractor’s three-point linkages were quantified with the assistance of a three-point hitch dynamometer, and tillage depth at the tractor rockshaft was measured using a rotary potentiometer. The obtained data exhibited exemplary results. This comprehensive and integrated system demonstrated the capability to measure, display and record real-time performance parameters, coupled with their precise geographical locations. The system underwent extensive and successful field demonstrations, particularly in the spatial mapping of tractor-implement field performance, utilizing a mounted offset disk harrow and a rigid tine cultivator.

Purpose: The study aims to provide insights on the practicality of using single-element transducers for transcranial Focused Ultrasound (tFUS) thermal applications. Methods: FUS sonications were performed through skull phantoms embedding agar-based tissue mimicking gels using a 1 MHz single-element spherically focused transducer. The skull phantoms were 3D printed with Acrylonitrile Butadiene Styrene (ABS) and Resin thermoplastics having the exact skull bone geometry of a healthy volunteer. The temperature field distribution during and after heating was monitored in a 3 T Magnetic Resonance Imaging (MRI) scanner using MR thermometry. The effect of the skull's thickness on intracranial heating was investigated. Results: A single FUS sonication at focal acoustic intensities close to 1580 W/cm2 for 60 s in free field heated up the agar phantom to ablative temperatures reaching about 90 °C (baseline of 37 °C). The ABS skull strongly blocked the ultrasonic waves, resulting in zero temperature increase within the phantom. Considerable heating was achieved through the Resin skull, but it remained at hyperthermia levels. Conversely, tFUS through a 1 mm Resin skull showed enhanced ultrasonic penetration and heating, with the focal temperature reaching 70 °C. Conclusions: The ABS skull demonstrated poorer performance in terms of tFUS compared to the Resin skull owing to its higher ultrasonic attenuation and porosity. The thin Resin phantom of 1 mm thickness provided an efficient acoustic window for delivering tFUS and heating up deep phantom areas. The results of such studies could be particularly useful for accelerating the establishment of a wider range of tFUS applications. [ABSTRACT FROM AUTHOR]

Microwave radiation has become an effective catalytic combustion method, especially in the degradation of volatile organic compounds (VOCs) such as toluene using catalysts like MnO2. In this study, a spine waveguide microwave reactor was designed to investigate the influence of different microwave processing conditions on the degradation of toluene catalyzed by MnO2. An experimental system for microwave-assisted catalytic degradation of toluene was established to explore the relationship between microwave power, catalyst conductivity, and toluene degradation rate. The results showed that the efficiency of MnO2 catalyzing toluene degradation had a nonlinear relationship with microwave power, first increasing to a peak and then decreasing. Additionally, the experiment found that the degradation rate of toluene was positively correlated with the conductivity of MnO2. Subsequent characterization analyses using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) further verified the changes in the microstructure and properties of MnO2 under microwave heating. The characterization results showed that with the increase in microwave power, the relative content of Mn3+ on the surface of MnO2 increased, and the relative content of adsorbed oxygen also increased accordingly. At a microwave power of 100 W, the treated MnO2 displayed the optimal ratio of manganese oxidation state and oxide, both close to 1:1, which was more conducive to the degradation of toluene. Based on these findings, this study hypothesized that the microwave-enhanced catalytic degradation of toluene by MnO2 may be attributed to changes in the surface electron transfer kinetics of MnO2, providing new insights into the field of microwave-enhanced catalysis. [ABSTRACT FROM AUTHOR]

The object of the upgrade presented in this paper was an older analogue-based universal testing machine preferably designed for tensile testing. The objective of the upgrade was to create a new digitized measurement chain capable of also operating in the mode of simple fatigue tests with cyclic tensile stresses. The upgrade of the equipment mainly included the processes of calibration, creation of related calibration jigs, creation of transformation dependencies and digitization, creation or completion of missing parts of chain-signal conditioning modules, A/D converters, special jigs, etc., as elements of the experimental hardware. The degree of correctness of the calibration and of the transformation dependencies created was verified by regression analysis, and this was verified by simple correlation analysis. The correctness of the proposed modifications, was verified on the basis of the fatigue tests performed for cyclic loading. Thus, it was possible to design, develop and functionally verify a new measurement chain based on an older universal testing machine. Thus, a partially digitized pulsator was created for the possibility of fatigue testing in a technically or functionally limited mode, mainly for educational purposes as a temporary replacement for the order of magnitude more expensive commercially produced test systems. [ABSTRACT FROM AUTHOR]

Two-dimensional ultrasound transducers enable the acquisition of fully volumetric data that have been demonstrated to provide greater diagnostic information in the clinical setting and are a critical tool for emerging ultrasound methods, such as super-resolution and functional imaging. This technology, however, is not without its limitations. Due to increased fabrication complexity, some matrix probes with disjoint piezoelectric panels may require initial calibration. In this manuscript, two methods for calibrating the element positions of the Vermon 1024-channel 8 MHz matrix transducer are detailed. This calibration is a necessary step for acquiring high resolution B-mode images while minimizing transducer-based image degradation. This calibration is also necessary for eliminating vessel-doubling artifacts in super-resolution images and increasing the overall signal-to-noise ratio (SNR) of the image. Here, we show that the shape of the point spread function (PSF) can be significantly improved and PSF-doubling artifacts can be reduced by up to 10 dB via this simple calibration procedure. [ABSTRACT FROM AUTHOR]

We present a new virtual laboratory developed with COMSOL multiphysics for the simulation of an acoustic levitator, as well as a three‐dimensional (3D) printed experimental setup. Our software application simulates the acoustic pressure field and its interaction with a set of particles. Students can interact with the system having the possibility to change the frequency and distance parameters between transducers in real time. We have also developed and shared for free use the 3D printing design files for the construction of the necessary components for the acoustic levitator, as well as the instructions for its experimental implementation. The experimental results are contrasted, along with those from the virtual laboratory, providing students with useful tools to understand and interpret the acoustic phenomenon in question. [ABSTRACT FROM AUTHOR]

One of the key advantages of Piezoelectric MEMS (PiezoMEMS) is its scalability, overcoming issues commonly associated with alternative transduction methods. However, the breadth and depth of studies on scaling the fabrication process from PiezoMEMS to NEMS (Nano-Electro-Mechanical Systems) remain limited. Effective MEMS miniaturization not only improves energy efficiency and surface area reduction but also enables the coupling of nanoscale physics, particularly Casimir Forces, with the NEMS design, device operation, and fabrication opportunities. Here, combined with the finite element method (FEM) modeling, the experimental aluminum nitride (AlN) nanotransducer fabrication is performed to address the fabrication challenges with beam-based in-plane nanostructures and to develop the piezoelectric NEMS design utilizing a controllable stiction behavior. The FEM modeling demonstrates that the designed structure featuring a 220 nm thick silicon (Si) beam with AlN layers located on vertical sidewalls exhibits controllable jump-to-contact and jump-off-contact behaviors. Based on modeling results, a complete piezoelectric sidewall transducer structure is fabricated. The final transducer represents a patterned Si nanobeam with the Molybdenum-AlN-Aluminum transducer located on the vertical sidewalls. The presented findings not only open new opportunities in the piezoelectric MEMS scaling but also establish a platform for the design of innovative “more-than-a-Moore” devices, such as in-plane mechanical latching switches.

This paper presents an experimental approach to maximizing the voltage generated by NaxCoO2 and improving the overall efficiency of the p-type thermoelectric leg by doping with Na up to x = 0.88. Two samples with different geometries were tested, each measured with and without an additional magnetic field applied in the direction of the temperature gradient. The properties of sodium cobaltite in response to hydration were explored, at temperatures between 300 and 380 K. Water injection boosted the current and power up to 75–100 µW at a temperature of 350–360 K. This power boost can be attributed to an electron-ion fluid flow pattern maintained by the longitudinal thermomagnetic effect and by water molecules forming hydrogen bonds with oxygen atoms in the CoO2 layers, inside the material. An electronic circuit was designed to boost the voltage to the desired level, for three or more sodium cobaltite samples mounted in parallel, and to store the energy in a supercapacitor. The output voltage and resistivity change of sodium cobaltite samples can be readily used as a humidity and temperature-sensing element in a transducer when paired with an appropriate electronic conditioning scheme.

This research is focused on enhancing the capabilities of scanning electrochemical impedance microscopy (SEIM) for detecting gold nanoparticle-labelled antibodies using electrochemically modified platinum ultramicroelectrode. The primary objective was to address the high resistance issue encountered in previous measurements with SEIM via the utilization of SEIM probes based on micro-electrodes modified by platinum microstructures, which improved the sensitivity and precision of the detection of targeted biomolecules. The modified probe resulted in a lowered charge transfer resistance by over ten times and a decrease in detection to around 100 fg/mL. We suggest potential applications in various biotechnological and biomedical fields, with future research expected to further refine this technique. [ABSTRACT FROM AUTHOR]

Cryogenic environments are increasingly used in scientific and industrial fields. Recently, cryogenic environments are also used for storage and supply of liquid hydrogen, which is considered essential for the realization of a decarbonized society. Actuators to drive a valve that controls such a low-temperature fluid are required. In this study, a piezoelectric transducer that can be driven in the cryogenic environment has been fabricated and evaluated. Although the performance of piezoelectric elements degrades at cryogenic temperatures in general, the application of a preload can suppress the degradation of performance. Equivalent circuits were used for evaluation, and force factors and figures of merit were compared. As a result, the force factor was as high as that at RT even at cryogenic temperatures, and a high figure of merit was obtained. The result indicates that the transducer can be used for the driving of micro actuator at cryogenic temperature. [ABSTRACT FROM AUTHOR]

The agricultural tractor serves as a pivotal power source on the farm. However, the optimal utilization of tractor power has often been hindered by factors such as non-matching implement sizes and suboptimal operating skills, leading to underutilization of power potential across diverse field conditions. In response, a study was initiated to formulate a cost-effective embedded system capable of on-the-go digital display and recording of various field performance parameters, ensuring precision in geographical location tracking. An embedded system, seamlessly incorporating a global positioning system (GPS), was successfully integrated onto an agricultural tractor to facilitate the mapping of tractor-implement performance. The developed embedded system employed Hall effect sensors for measuring theoretical speeds at both tractor rear drive wheels, as well as the actual speed at the tractor front wheel. Additionally, forces at the tractor's three-point linkages were quantified with the assistance of a three-point hitch dynamometer, and tillage depth at the tractor rockshaft was measured using a rotary potentiometer. The obtained data exhibited exemplary results. This comprehensive and integrated system demonstrated the capability to measure, display and record real-time performance parameters, coupled with their precise geographical locations. The system underwent extensive and successful field demonstrations, particularly in the spatial mapping of tractor-implement field performance, utilizing a mounted offset disk harrow and a rigid tine cultivator. [ABSTRACT FROM AUTHOR]

Purpose: Nature and occurrence of food-borne pathogens in raw and processed food products evolved greatly in the past few years due to new modes of transmission and resistance build-up against sundry micro-/macro-environmental conditions. Assurance of food health and safety thus gained immense importance, for which bio-sensing technology proved very promising in the detection and quantification of food-borne pathogens. Considering the importance, different studies have been performed, and different biosensors have been developed. This study aims to summarize the different biosensors used for the deduction of food-borne pathogens. Design/methodology/approach: The present review highlights different biosensors developed apropos to food matrices, factors governing their selection, their potential and applicability. The paper discusses some related key challenges and constraints and also focuses on the needs and future research prospects in this field. Findings: The shift in consumers' and industries' perceptions directed the further approach to achieve portable, user and environmental friendly biosensing techniques. Despite of these developments, it was still observed that the comparison among the different biosensors and their categories proved tedious on a single platform; since the food matrices tested, pathogen detected or diagnosed, time of detection, etc., varied greatly and very few products have been commercially launched. Conclusively, a challenge lies in front of food scientists and researchers to maintain pace and develop techniques for efficiently catering to the needs of the food industry. Research limitations/implications: Biosensors deduction limit varied with the food matrix, type of organism, material of biosensors' surface, etc. The food matrix itself consists of complex substances, and various types of food are available in nature. Considering the diversity of food there is a need to develop a universal biosensor that can be used for all the food matrices for a pathogen. Further research is needed to develop a pathogen-specific biosensor that can be used for all the food products that may have accuracy to eliminate the traditional method of deduction. Originality/value: The present paper summarized and categorized the different types of biosensors developed for food-borne pathogens. [ABSTRACT FROM AUTHOR]

The paper introduces the concept of a transducer base for HUMS of the suspension system of a high mobility wheeled vehicle. The basic principles of the maintenance system with HUMS as a subsystem and its structure are clarified. The main benefits for operators of the maintenance system after implementation of HUMS into vehicles are presented. Preliminary ranges of loads to be monitored, generated in a selected point in the suspension system of a vehicle with a GVW of 3.5T class are presented, as well as general dimensions and material selection for the base of the transducer. [ABSTRACT FROM AUTHOR]

The operation of working machines is accompanied by the constant occurrence of vibrations and shocks, generated by various constructive, kinematic and dynamic factors. The study of the vibro-acoustic aspect of mechanical transmissions and, in particular, of precessional planetary ones is a primary concern for engine ers in the field of machine building technologies. The paper presents the research of precessional planetary transmissions under the vibro-aco ustic aspect in the anechoic chamber, which is a room, in sulated with sound-absorbing material against external noises and isolated anti-vibration. To process the vibro-acoustic signals received as a result of the measurements, the Fourier harmonic series will be applied, a mathematical function that can be used to find the basic frequencies that make up a wave. The final result is the detection of vibration and noise generating sources, the decoding of signals by means of Fourier series and the advancement of constructive-technological solutions to minimize the vibro-acoustic level.

An all‐solid‐state impedance metric hydrogen‐phosphate ion sensor device has been tried to fabricate using BaTiO3 as a transducer and spinel‐type oxide receptor. AC impedance measurement was carried out using flow‐cell system with boric‐acid buffer solution with hydrogen‐phosphate ion The Co2RhO4/BaTiO3 sensor device was found to show impedance responses to hydrogen‐phosphate ion at 5 × 10−4 M and 1.0 × 10−2 M with the 90% response time of ca. 150 s. The Co2RhO4/BaTiO3 device showed good response characteristics among the tested devices in terms of sensitivity and restoration rate. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Accurate measurement of the pretightening stress for bolts has great significance for improving the assembly quality and safety, especially in severe environments. In this study, AlN thin film transducers were deposited on GH4169 nickel base alloy bolts using the RF magnetron sputtering, enabling a systematic investigation into the correlation between structures and the intensity of ultrasonic echo signals. Employing the finite element method resulted in consistency with the experimental data, enabling further exploration of the enhancement mechanism. With the increasing thickness of both the piezoelectric layer and the electrode layer, the intensity of the ultrasonic echo signals saw a great enhancement. The maximum-intensity observed increase is 14.7 times greater than that of the thinnest layers. Specifically, the thicker piezoelectric layer improves its mechanical displacement, while the increased thickness of the electrode layer contributes to better densification. An electrode diameter of nearly 4 mm is optimal for an AlN thin film transducer of M8 bolts. For pretightening the stress measurement, the sample with a strong and stable echo signal shows a low measurement error of pretightening below ±2.50%.

Medical ultrasound has emerged as an indispensable tool within interventional pulmonology, revolutionizing diagnostic and procedural practices through its non-invasive nature and real-time visualization capabilities. By harnessing the principles of sound waves and employing a variety of transducer types, ultrasound facilitates enhanced accuracy and safety in procedures such as transthoracic needle aspiration and pleural effusion drainage, consequently leading to improved patient outcomes. Understanding the fundamentals of ultrasound physics is paramount for clinicians, as it forms the basis for interpreting imaging results and optimizing interventions. Thoracic ultrasound plays a pivotal role in diagnosing conditions like pleural effusions and pneumothorax, while also optimizing procedures such as thoracentesis and biopsy by providing precise guidance. Advanced ultrasound techniques, including endobronchial ultrasound, has transformed the evaluation and biopsy of lymph nodes, bolstered by innovative features like elastography, which contribute to increased procedural efficacy and patient safety. Peripheral ultrasound techniques, notably radial endobronchial ultrasound (rEBUS), have become essential for assessing pulmonary nodules and evaluating airway structures, offering clinicians valuable insights into disease localization and severity. Neck ultrasound serves as a crucial tool in guiding supraclavicular lymph node biopsy and percutaneous dilatational tracheostomy procedures, ensuring safe placement and minimizing associated complications. Ultrasound technology is suited for further advancement through the integration of artificial intelligence, miniaturization, and the development of portable devices. These advancements hold the promise of not only improving diagnostic accuracy but also enhancing the accessibility of ultrasound imaging in diverse healthcare settings, ultimately expanding its utility and impact on patient care. Additionally, the integration of enhanced techniques such as contrast-enhanced ultrasound and 3D imaging is anticipated to revolutionize personalized medicine by providing clinicians with a more comprehensive understanding of anatomical structures and pathological processes. The transformative potential of medical ultrasound in interventional pulmonology extends beyond mere technological advancements; it represents a paradigm shift in healthcare delivery, empowering clinicians with unprecedented capabilities to diagnose and treat pulmonary conditions with precision and efficacy. By leveraging the latest innovations in ultrasound technology, clinicians can navigate complex anatomical structures with confidence, leading to more informed decision-making and ultimately improving patient outcomes. Moreover, the portability and versatility of modern ultrasound devices enable their deployment in various clinical settings, from traditional hospital environments to remote or resource-limited areas, thereby bridging gaps in healthcare access and equity.