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OBJECTIVES: Systemic arterial hypertension is a common occurrence and can have serious adverse consequences in cats. Therefore, measuring blood pressure is very important. There are many indirect blood pressure measurement devices available. This study compared Doppler, oscillometric (petMAP Graphic II, SunTech Vet20, the Cardell Insight-X0000) and high-definition oscillometry devices for the non-invasive measurement of blood pressure in conscious cats.METHODS: In this prospective study, blood pressure was measured in 32 cats using the different devices according to the recommendations of the American College of Veterinary Internal Medicine Consensus Statement. Blood pressures (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP]), time to complete measurements, number of attempts needed, coefficient of variation (CV) between the blood pressure measurements of the different devices, ease of completing measurements and apparent stress level of the cat were assessed.RESULTS: There was a significant difference between devices in the time taken to obtain blood pressure readings and the number of attempts necessary to obtain six reliable measurements. The CV of the Doppler device was significantly smaller than that of the rest of the devices, but there were no other differences between the devices. The mean SBP, DBP and MAP measured by the petMAP device were significantly higher than the measurements from the other devices. The perceived ease of measurement was not significantly different between the various machines. The perceived level of stress of measurement with the Doppler device was significantly higher compared with the other devices but did not lead to an increased SBP.CONCLUSIONS AND RELEVANCE: Using a Doppler device to measure blood pressure in conscious cats is fast, relatively easy and gives reliable results. A disadvantage is that the Doppler device can only measure SBP, while oscillometric devi

The focus of this thesis is to scale down single beam acoustic tweezers to achieve lower particle manipulation sizes and to explore applications with the scaled devices. The first chapter of this thesis explores the literature review relative to the scientific foundations of acoustic manipulation. It also explores the current technologies researched respective to acoustic patterning, as well as for acoustic single particle manipulation. The second chapter presents the research undertaken in this work to scale-down single beam acoustic tweezers. Here, the theory and the methods relative to the construction of the device and the steps to achieve single particle manipulation are described. New applications are also explored such as, manipulating particles and organoids through a petri-dish and a plastic micro-tube. Also a method was implemented to visualise high and low pressure regions of the acoustic field. As a result, acoustic manipulation of a single 130-micrometer diameter particle was achieved in 3 spatial dimensions. Additionally, manipulation of a 32-micrometer diameter particle was achieved with a 4.32 MHz twin-trap. Acoustic manipulation of a 920-micrometer embryonic stem cell organoid was also achieved. The maximum acoustic pressure achieved in the 1.76 MHz twin trap device was measured as 238 kPa. The radiation force within this trap was found to be 0.38 µN for an excitation level of 14 Vpp (peak to peak volts). In the third chapter of this thesis, the steps, theory and methods to achieve the rotation of an intraocular lens (IOL) are described. Additionally, the initial trials of rotation by using acoustic radiation force are explored. Furthermore, it is concluded that acoustic streaming was found to achieve a better control-ability for achieving the rotation of the IOL. These results suggest a promising future incorporation of the devices built in this work into the biology and medical sectors.

Our purpose was to test the hypothesis that ultrasonic cigarettes (u-cigarettes), which operate at relatively low temperatures, produce aerosols that are less harmful than heated-coil pod-style electronic cigarettes (e-cigarettes). The major chemicals in SURGE u-cigarette fluids and aerosols were quantified, their cytotoxicity and cellular effects were assessed, and a Margin of Exposure risk assessment was performed on chemicals in SURGE fluids. Four SURGE u-cigarette flavor variants (Blueberry Ice, Watermelon Ice, Green Mint, and Polar Mint) were evaluated. Flavor chemicals were quantified in fluids and aerosols using gas chromatography/mass spectrometry. Cytotoxicity and cell dynamics were assessed using the MTT assay, live-cell imaging, and fluorescence microscopy. WS-23 (a coolant) and total flavor chemical concentrations in SURGE were similar to e-cigarettes, while SURGE nicotine concentrations (13-19 mg/mL) were lower than many fourth generation e-cigarettes. Transfer efficiencies of dominant chemicals to aerosols in SURGE ranged from 44-100%. SURGE fluids and aerosols had four dominant flavor chemicals (>1 mg/mL). Toxic aldehydes were usually higher in SURGE aerosols than in SURGE fluids. SURGE fluids and aerosols had aldehyde concentrations significantly higher than pod-style e-cigarettes. Chemical constituents, solvent ratios, and aldehydes varied among SURGE flavor variants. SURGE fluids and aerosols inhibited cell growth and mitochondrial reductases, produced attenuated and round cells, and depolymerized actin filaments, effects that depended on pod flavor, chemical constituents, and concentration. The MOEs for nicotine, WS-23, and propylene glycol were <100 based on consumption of 1-2 SURGE u-cigarettes/day. Replacing the heating coil with a sonicator did not eliminate chemicals, including aldehydes, in aerosols or diminish toxicity in comparisons between SURGE and other e-cigarette pod products. The high concentrations of nicotine, WS-23, flavor c

The cellulose pulp refining process is crucial for achieving high-quality paper characteristics. This research aims to enhance energy efficiency while maintaining good fiber quality using hydrodynamic and acoustic cavitation (HAC). Experiments were conducted with an in-house developed flow-through sonicator combined with a novel Venturi nozzle for hydrodynamic cavitation. The Venturi design was determined by analytical modeling and verified by CFD simulation with multi-phase turbulence models to balance cavitation intensity and turbulence against the acoustic cavitation effect. Experimental evaluation of two batches of CTMP fibers, pre-processed in different ways, showed significant improvements in paper strength and fiber properties. The best results for Batch 1 (HC and LC) were obtained with 386 kWh/bdt for AC and 350 kWh/bdt for HC (60 °C, 2 % concentration). The tensile strength index increased by 26 %, and the TEA-index, related to freeness, increased by 55 %. HAC treatment (750 kWh/bdt, 70 °C, 1.5 % concentration) of the less refined Batch2 (HC) yielded results better than the Batch 1 reference. These findings confirm the energy-efficient potential of the sonicator concept compared to traditional industrial processes. The conclusion is that HAC-refining of softwood pulp requires a proper balance between hydrodynamic and acoustic cavitation intensities. Both fiber concentration by weight and temperature are critical for an energy-efficient process., Validerad;2024;Nivå 2;2024-08-06 (hanlid);Full text license: CC BY;This article has previously appeared as a manuscript in a thesis.

The naringin extraction process was optimised using response surface methodology (RSM). A central component design was adopted, which included four parameters: extraction temperature (X1), material-liquid ratio (X2), extraction time (X3), and ultrasonic frequency (X4) of 74.79 °C, 1.58 h, 1:56.51 g/mL, and 28.05 KHz, respectively. Based on these optimal extraction conditions, naringin was tested to verify the model's accuracy. Naringin yield was 36.2502 mg/g, which was equivalent to the predicted yield of 36.0124 mg/g. DM101 macroporous adsorption resin was used to purify naringin. The effects of loading concentration, loading flow rate, and sample pH on the adsorption rate of naringin and the effect of ethanol concentration on the desorption rate of naringin were investigated. The optimum conditions for naringin purification using macroporous resins were determined. The optimal loading concentration, sample solution pH, and loading flow rate were 0.075 mg/mL, 3.5, and 1.5 mL/min, respectively. Three parallel tests were conducted under these conditions, and the average naringin yield was 77.5643%. Naringin's structure was identified using infrared spectroscopy and nuclear magnetic resonance. In vitro determination of the lipid-lowering activity of naringin was also conducted. These results showed that naringin has potential applications as a functional food for lowering blood lipid levels.

Weight savings in mobility and transport are mandatory in order to reduce CO 2 emissions and energy consumption. The steel industry offers weight saving solutions by a growing portfolio of Advanced High Strength Steel (AHSS) products. AHSS owe their strength to their largely refined and complex microstructures, containing multiple metallurgical phases. Optimal control of the thermo-mechanical processing of AHSS requires inline sensors for real-time monitoring of evolution and consistency of microstructure and material properties. To coordinate and accelerate European development activities in this domain, the project ¿Online Microstructure Analytics (OMA)¿ was established in 2019, constituting of a consortium of 14 specialised research organisations. The EU-funded OMA project, with a total budget exceeding 6 MEU, focuses on inline sensing techniques to monitor the consistency and homogeneity of microstructure, texture and mechanical properties for automotive steels and in particular for AHSS.

Advances in ultrasonic nonlinear imaging techniques have increased the detectability of fatigue cracks during earlier stages of formation. This thesis explores the novel nonlinear ultrasonic diffuse energy imaging (NUI) technique used for non-destructive testing (NDT). In contrast to current linear methods the NUI method is able to image tightly closed crack tips and quantify the degree of nonlinearity present in the defect without the need for mechanical scanning or complicated bespoke set-ups. More specifically, unlike nonlinear coherent methods the NUI method is able to resolve nonlinear closed crack tips without the need for coherent reflections from damage, meaning the orientation of the crack tips is not required and the method can be extended to classical nonlinearity induced by lattice anharmonicity and dislocations. A sensitivity analysis of the NUI technique is first explored to establish the sensitivity profile of the method and further understand the detectability of nonlinear features in materials. This is achieved through experimental and simulated data, and explores the influence of attenuation and transmission frequency on detectability of nonlinear features. Consistent sensitivity over the frequency transmission range investigated is observed and is attributed to the competing effects of increased attenuation and nonlinearity as frequency increases. The knowledge of the sensitivity profile is then used to investigate a multi-view diffuse method to allow optimisation of the position of the sensitivity profile used to detect the nonlinear feature. This is only effective at 5 MHz where a nonlinear feature is detected very close to the array which is otherwise undetectable using the existing single-view NUI technique. Further optimisations of the NUI technique are investigated. Firstly, a multi-frequency adaptation is explored and compares the sensitivity of the NUI technique using varying transmission frequencies and receiving at di

Ultrasound provides a way to clean fouled pipes in industrial settings without interrupting the production. Ultrasonic clamp-on cleaners are used to clean pipes, but they typically cannot focus the cleaning power. This leads to insufficient cleaning results in cases where the fouling is localized to certain parts of the pipe. To solve this issue, we propose a finite-element method -based time-reversal (FEM-TR) technique for controlling the acoustic field produced by an ultrasonic clamp-on cleaner. We demonstrate by simulations and experimental validation that FEM-TR can be used to control the acoustic field in clamp-on cleaners featuring relatively few narrow-band and high-power transducers. The proposed method allows us to focus sound to arbitrary pre-selected locations inside the structure. © 2022 The Authors

Ultrasonics is new science that is being intensively developed in recent years. Sound velocity is a valuable engineering tool and non-destructive, non-invasive, non-intrusive technique of measurement. The authors were highly motivated to collect data from as many research papers as possible in order to see the possibilities and examples of applying this technology. The various effects of ultrasound were discussed and outlined in a context of different uses to accelerate or support agricultural production processes like: the effects of ultrasound waves, the commercial and diagnostical applications possibilities. The field of biotechnical engineering is very multidisciplinary and, accordingly, there is a diversity in approaches and possibilities of applying ultrasound. The overall conclusion of our work is that the use of ultrasound in biotechnical research brings various benefits, and in some cases, it is extremely supported and recommended. Also, there is great flexibility in the ways in which this technology can be applied, which leaves engineers a lot of freedom in expressing creative solutions and applications.

Rats emit ultrasonic vocalizations in a variety of appetitive and aversive contexts. Although the reason why these calls are emitted is yet unknown, two prominent theories exist, the affective state theory and the social communication theory. This thesis will provide evidence to support the theory that these calls are emitted as a form of social communication. Four experiments will be presented, each testing a facet of the social communication theory. These experiments provide evidence that the calls are linked to social stimuli over non-social reward, and are emitted in divergent patterns depending on strain, regardless of depressive state. Further, they demonstrate that not all appetitive rewards elicit the same calling response, and that the calls emitted have a direct impact on conspecific behaviour. Overall, it is concluded that, although some vocalizations may be an indicator of the rat’s affective state, they are also used as a form of social communication.

Introduction: Intravascular bubble load after decompression can be detected and scored using ultrasound techniques that measure venous gas emboli (VGE). The aim of this study was to analyse the agreement between ultrasonic bubble grades from a handheld self-positioning product, the O’Dive™, and cardiac 2D ultrasound after decompression. Methods: VGE were graded with both bilateral subclavian vein Doppler ultrasound (modified Spencer scale) and 2D cardiac images (Eftedal Brubakk scale). Agreement was analysed using weighted kappa (Kw ). Analysis with Kw was made for all paired grades, including measurements with and without zero grades, and for each method’s highest grades after each dive. Results: A total of 152 dives yielded 1,113 paired measurements. The Kw agreement between ultrasound VGE grades produced by cardiac 2D images and those from the O’Dive was ‘fair’; when zero grades were excluded the agreement was ‘poor’. The O’Dive was found to have a lower sensitivity to detect VGE compared to 2D cardiac image scoring. Conclusions: Compared to 2D cardiac image ultrasound, the O’Dive yielded generally lower VGE grades, which resulted in a low level of agreement (fair to poor) with Kw . © South Pacific Underwater Medicine Society and the European Underwater and Baromedical Society.

Nanoscale wireless networks are expected to revolutionize a variety of domains, with significant advances conceivable in in-body healthcare. These nanonetworks will consist of energy-harvesting nanodevices passively flowing through the bloodstream, taking actions at certain locations, and communicating results to a more powerful Body Area Network (BAN). Assuming such a setup and electro-magnetic nanocommunication in the Terahertz (THz) frequencies, we propose a network architecture that can support fine-grained localization of the energy-harvesting in-body nanonodes, as well as their two-way communication with the outside world. The main novelties of our proposal lie in the utilization of location-aware and Wake-up Radio (WuR)-based wireless nanocommunication paradigms, as well as Software-Defined Metamaterials (SDMs), for supporting the envisioned functionalities in THz-operating energy-harvesting in-body nanonetworks. We argue that, on a high level, the proposed architecture can handle a large number of nanonodes, while simultaneously dealing with a short range of THz in-body propagation and highly constrained nanonodes., The author Filip Lemic was supported by the EU Marie Curie Actions Individual Fellowship project Scalable Localization-enabled In-body Terahertz Nanonetwork (SCaLeITN), grant nr. 893760., Peer Reviewed, Postprint (author's final draft)

The detection of rebar corrosion in reinforced concrete is important due to the high costs of corrosion related damages to infrastructure. One such method of rebar corrosion lies in the use of non-destructive ultrasonic testing. To date, acoustic methods require either the training of an artificial neural network or a theory of acoustic wave propagation. Using a more complete acoustic model such as the Biot-Stoll model avoids algorithm training requirements by directly modeling the acoustic environment. A problem with this method lies in the complexity of the model and the selection of free parameters. The problem of parameter selection is addressed by a series of targeted measurements using ultrasonic transducers on a set of existing reinforced concrete samples placed in a saltwater solution. This data can then be analyzed by a non-linear least squares solver to produce a better fit for the acoustic signal., 2022, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2022., Collection: FAU Electronic Theses and Dissertations Collection

El projecte es centrarà en un sistema de balises basades en ultrasons. La principal funcionalitat que es busca en el projecte, és el fet de poder comunicar dos dispositius, que anomenarem balises, amb els quals poder determinar la distància a què es troba un de l'altre en un pla d'una dimensió. Aquesta comunicació serà possible mitjançant dos mòduls de radiofreqüència, un per a la transmissió i un altre per a la recepció. Per altre banda, una emissió de senyal d'ultrasons amb què calcular la distància mitjançant la diferència de temps d'arribada entre el senyal de radiofreqüència i la d'ultrasons., El proyecto se centrará en un sistema de balizas basadas en ultrasonidos. La principal funcionalidad que se le busca al proyecto, es el hecho de poder comunicar dos dispositivos, que denominaremos balizas, con los que poder determinar la distancia a la que se encuentra uno del otro en un plano de una dimensión. Esta comunicación será posible mediante dos módulos de radiofrecuencia, uno para la transmisión y otro para la recepción. Por otra banda, una emisión de señal de ultrasonidos con la que calcular la distancia mediante la diferencia de tiempos de llegada entre la señal de radiofrecuencia y la de ultrasonidos., The project will focus on a beacon system based on ultrasounds. The main functionality that is sought for the project is the fact of being able to communicate two devices, which we will call beacons, with which to be able to determine the distance at which one is from the other in a one-dimensional plane. This communication will be possible through two radiofrequency modules, one for transmission and one for reception. On the other hand, an ultrasound signal emission with which to calculate the distance by means of the difference in arrival times between the radiofrequency signal and the ultrasound signal.

Acoustofluidics has promised to enable lab-on-a-chip and point-of-care devices in ways difficult to achieve using other methods. Piezoelectric ultrasonic transducers-as small as the chips they actuate-provide rapid fluid and suspended object transport. Acoustofluidic lab-on-chip devices offer a vast range of benefits in early disease identification and noninvasive drug delivery. However, their potential has long been undermined by the need for benchtop or rack-mount electronics. The piezoelectric ultrasonic transducers within require these equipment and thus acoustofluidic device implementation in a bedside setting has been limited. Here we detail a general process to enable the reader to produce battery or mains-powered microcircuits ideal for driving 1-300 MHz acoustic devices. We include the general design strategy for the circuit, the blocks that collectively define it, and suitable, specific choices for components to produce these blocks. We furthermore illustrate how to incorporate automated resonance finding and tracking, sensing and feedback, and built-in adjustability to accommodate devices' vastly different operating frequencies and powers in a single driver, including examples of fluid and particle manipulation typical of the needs in our discipline. With this in hand, the many groups active in lab-on-a-chip acoustofluidics can now finally deliver on the promise of handheld, point-of-care technologies.

In all ultrasonic material evaluation methods, transducers and sensors play a key role of mechanoelectrical conversion. Their transduction characteristics must be known quantitatively in designing and implementing successful structural health monitoring (SHM) systems. Yet, their calibration and verification have lagged behind most other aspects of SHM system development. This study aims to extend recent advances in quantifying the transmission and receiving sensitivities to normally incident longitudinal waves of ultrasonic transducers and acoustic emission sensors. This paper covers extending the range of detection to lower frequencies, expanding to areal and multiple sensing methods and examining transducer loading effects. Using the refined transmission characteristics, the receiving sensitivities of transducers and sensors were reexamined under the conditions representing their actual usage. Results confirm that the interfacial wave transmission is governed by wave propagation theory and that the receiving sensitivity of resonant acoustic emission sensors peaks at antiresonance.

Ultrasound modulates the electrical activity of excitable cells and offers advantages over other neuromodulatory techniques; for example, it can be noninvasively transmitted through the skull and focused to deep brain regions. However, the fundamental cellular, molecular, and mechanistic bases of ultrasonic neuromodulation are largely unknown. Here, we demonstrate ultrasound activation of the mechanosensitive K+ channel TRAAK with submillisecond kinetics to an extent comparable to canonical mechanical activation. Single-channel recordings reveal a common basis for ultrasonic and mechanical activation with stimulus-graded destabilization of long-duration closures and promotion of full conductance openings. Ultrasonic energy is transduced to TRAAK through the membrane in the absence of other cellular components, likely increasing membrane tension to promote channel opening. We further demonstrate ultrasonic modulation of neuronally expressed TRAAK. These results suggest mechanosensitive channels underlie physiological responses to ultrasound and could serve as sonogenetic actuators for acoustic neuromodulation of genetically targeted cells.

The aim of this study wasto compare the influence of a final rinse with and without passive ultrasonic irrigation (PUI), using 17% ethylenediamine-tetraacetic acid (EDTA) or 10% citric acid (CA), with 2.5% sodium hypochlorite (NaOCl) with PUI, on the sealing ability of root canal fillings. Root canal instru-mentation was performed in single-rooted premolars using NaOCl as the irrigant. Subsequently, the roots were randomly allocated into four experimental groups (n=23): EDTA+PUI, EDTA, CA+PUI, CA and control group: NaOCl+PUI. The spec-imens were root-filled using gutta-percha with a resin-based sealer and inserted into a device to measure glucose leakage at 7 and 30 days. Kruskal-Wallis and Mann-Whitney tests were used to evaluate the differences between the solutions and with or without PUI. Friedman’s ANOVA was used to compare time points (P<0.05). PUI groups showed lower infiltration values (EDTA+PUI 0.74±0.77 and CA+PUI 5.32±1.45) when compared to the groups on which PUI was not performed (EDTA 7.20±2.18 and CA 20.73±4.70), this difference was significant for EDTA (P<0.01) and CA (P=0.000). Also, EDTA showed less glucose infiltration than CA, with or without PUI (P<0.005). NaOCl+PUI showed a higher cumulative glucose infiltra-tion (22.92±9.71). A final rinse using EDTA or CA with PUI enhances the sealing of root canal fillings. EDTA showed less infiltration., El objetivo de este estudio fue comparar la influencia de una irrigación final con o sin activación ultrasónica pasiva (PUI), utilizando ácido etilendiaminotetraacético (EDTA) al 17% o ácido cítrico (CA) al 10%, con hipo-clorito de sodio (NaOCl) al 2,5% con PUI, sobre el sellado de la obturación de conductos radiculares. Después de la instrumentación utilizando NaOCl como irrigante, premolares de raíz única se asignaron aleatoriamente a cuatro grupos experimentales (n = 23): EDTA+PUI, EDTA, CA+PUI, CA y grupo de control: NaOCl+PUI. Los conductos se obturaron utilizando gutapercha con un sellador a base de resina y se insertaron en un dispositivo para medir la infiltración de glucosa a los 7 y 30 días. Se utilizaron las pruebas de Kruskal-Wallis y Mann-Whit-ney para evaluar las diferencias entre las soluciones y con o sin PUI. Se utilizó el ANOVA de Friedman para comparar los puntos temporales (P <0,05). Los gru-pos de PUI mostraron menores valores de infiltración (EDTA+PUI 0,74±0,77 y CA+PUI 5,32±1,45) en comparación con los grupos en los que no se realizó PUI (EDTA 7,20±2,18 y CA 20,73±4,70), esta diferencia fue significativa para EDTA (P <0,01) y CA (P = 0,000). Además, EDTA mostró menos infiltración de glucosa que CA, con o sin PUI (P <0,005). NaOCl+PUI mostró una mayor infiltración acumulada de glucosa (22,92±9,71). Una irrigación final con EDTA o CA con PUI mejora el sellado de la obturación de conducto radicular. EDTA mostró menos infiltración.

Soft robotics is a promising field that can solve several limitations of traditional rigid robotics. These systems are composed of soft and flexible materials to achieve high degrees-of-freedom and compliance with their surroundings. An important part of soft robotics is developing methods to actuate the soft structures. A popular method involves inflating soft hollow structures with a pneumatic pump that can achieve rapid and precise actuation. However, the structure must be tethered to a heavy and rigid pump, which limits its application. An alternative method vaporizes embedded liquid to inflate the structure instead. The simplest and widely used design to vaporize such liquid is by installing a heating element near the liquid. Heating the system beyond the boiling point rapidly boils the liquid and deforms the structure. The small amount of liquid and heater makes it easier to be packaged into a portable device. Nevertheless, this technique possesses several limitations that must be improved to be practical. This dissertation addresses these limitations and introduces methods that can advance the field for future robotics. Chapter 2 describes how actuation through vaporization can be affected by the environment and introduces a system that consists of double-layered walls and a thermoelectric device. Chapter 3 aims to implement ultrasonic waves that propagate through materials, which enables a system with detachable parts. Chapter 4 utilizes vibrating mesh atomization to drastically improve the slow actuation speed by evaporating small droplets with large surface areas. Last, chapter 5 introduces a method that can potentially remove electrical components by combining ultrasonics with shape optimization. These studies show that soft actuation through vaporization has significant room for improvement and can potentially replace commercial actuation methods with further optimization.

Slow pyrolysis is widely used to convert biomass into useable form of energy. Ultrasound pre-treatment assisted pyrolysis is a recently emerging methodology to improve the physicochemical properties of products derived. Biochar, the solid residues obtained from pyrolysis, is getting considerable attention because of its good physicochemical properties. Various modification techniques have been implemented on biochars to enhance their properties. Ultrasonic pre-treated wood biochar has showcased efficient surface and adsorption properties. Iron impregnated biochar is interesting as it has potentially proved the efficiency as an efficient low-cost catalyst. In this study, by combining the advantages of ultrasonic pre-treatment and iron impregnation, we have synthesized a series of Fe-impregnated biochar from softwood chips. Pre- and post-pyrolysis methods using a lab-scale pyrolyser had been implemented to compare the pyrolysis product yields and degree of impregnation. Biochars derived from ultrasound pre-treated woodchips by post pyrolysis demonstrated better impregnation of Fe ions on surface with better distribution of pyrolysis products such as biochar and biogas. The surface functionality of all ultrasound pre-treated biochars remained the same. However, post-pyrolysed samples at high frequency ultrasound pre-treatment showed better thermal stability. The chemical characteristics of these modified biochars are interesting and can indeed be used as a cost-effective replacement for various catalytic applications. © 2021, The Author(s).

Physical and chemical modification on biochar is an interesting approach to enhance the properties and make them potential candidates in adsorption of heavy metals from water. Studies have shown that ultrasound treatments as well as alkali activations on biochar has positive impact on adsorption behaviour of the material. Base activation on biochar derived from ultrasound pre-treated woodchips were studied to understand the influence of ultrasound pre-treatment on chemical modification of biochar and the adsorption properties emerged from it. 40 and 170 kHz ultrasound pre-treated softwood woodchips were subjected to laboratory scale pyrolysis and the resulted biochars were treated with NaOH. The physicochemical properties were examined, and the adsorption experiments revealed that ultrasound pre-treatment assisted biochars have better adsorption capacity as compared to untreated biochar samples after activation. 170 kHz pre-treated sample exhibited an equilibrium adsorption capacity of 19.99 mg/g which is almost 22 times higher than that of corresponding non-activated sample. The ultrasound pre-treated samples showed improved competitive adsorption behaviour towards copper ions in comparison with nickel or lead. The overall study suggests that ultrasound pre-treated biochars combined with alkali activation enhances the heavy metal removal efficiency and these engineered biochars can be used as an effective adsorbent in the field of wastewater treatment. © 2021 Elsevier Ltd

One of the most significant tasks of echocardiography is the automatic delineation of the cardiac structures from 2D echocardiographic images. Over the past decades, the automation of this taskhas been the subject of intense research. One of the most effective approaches is based on the deepconvolutional neural networks. Nonetheless, it is necessary to use echocardiogram frames of the cardiac muscle, which show the boundaries of the cardiac structures labeled/annotated by experts/cardiologists to train it. However, the number of databases containing the necessary information is relatively small. Therefore, generated echocardiogram frames are used to increase the amount of training samples. This process is based on the ultrasound images of the heart, annotated by experts. The article proposes an improved method for generating echocardiograms using a generative adversarial neural network (GAN) with a patch-based conditional discriminator. It has been demonstrated that it is possible to improve the quality of generated echocardiogram frames in both two and four chamber views (AP4C, AP2C) using the masks of cardiac segmentation with sub-pixel convolution layer (pixel shuffle). It is demonstrated that the proposed approach makes it possible to generate ultrasound images, the structure of which corresponds to the specified segmentation masks. It is expected that this method will improve the accuracy of solving the direct problem of automatic segmentation of the left ventricle. © Published under licence by IOP Publishing Ltd.

Conversion of glass slides to digital images is necessary to capitalize on advances in computational pathology and could potentially transform our approach to primary diagnosis, research, and medical education. Most slide scanners have a limited maximum scannable area and utilize proprietary tissue detection algorithms to selectively scan regions that contain tissue, allowing for increased scanning speed and reduced file size compared to scanning the entire slide at high resolution. However, very small and faintly stained tissue fragments may not be recognized by these algorithms, leading to loss of fidelity in the digital image compared to the glass slides. Cavitron ultrasonic surgical aspirator (CUSA) is frequently used in brain tumor resections, resulting in highly fragmented specimens that are used for primary diagnosis. Here we evaluated the rate of loss of fidelity in 296 digital images from 40 CUSA-resected brain tumors scanned using a Philips Ultra Fast Scanner. Overall, 54% of the slides (at least one from every case) showed loss of fidelity, with at least one tissue fragment not scanned at high resolution. The majority of the missed tissue fragments were small (<0.5 mm), but rare slides were missing fragments greater than 5 mm in greatest dimension. In addition, 19% of the slides with missing tissue showed no indication of loss of fidelity in the digital image itself; the missing tissue could only be appreciated upon review of the glass slides. These results highlight a potential liability in the use of digital images for primary diagnosis in CUSA-resected brain tumor specimens.

Acoustic radiation force optical coherence elastography (ARF-OCE) has been successfully implemented to characterize the biomechanical properties of soft tissues, such as the cornea and the retina, with high resolution using single-element ultrasonic transducers for ARF excitation. Most currently proposed OCE techniques, such as air puff and ARF, have less capability to control the spatiotemporal information of the induced region of deformation, resulting in limited accuracy and low temporal resolution of the shear wave elasticity imaging. In this study, we propose a new method called 2-D ultrasonic array-based OCE imaging, which combines the advantages of 3-D dynamic electronic steering of the 2-D ultrasonic array and high-resolution optical coherence tomography (OCT). The 3-D steering capability of the 2-D array was first validated using a hydrophone. Then, the combined 2-D ultrasonic array OCE system was calibrated using a homogenous phantom, followed by an experiment on ex vivo rabbit corneal tissue. The results demonstrate that our newly developed 2-D ultrasonic array-based OCE system has the capability to map tissue biomechanical properties accurately, and therefore, has the potential to be a vital diagnostic tool in ophthalmology.

ObjectiveChanges in ultrasound backscatter energy (CBE) imaging can monitor thermal therapy. Catheter-based ultrasound (CBUS) can treat deep tumors with precise spatial control of energy deposition and ablation zones, of which CBE estimation can be limited by low contrast and robustness due to small or inconsistent changes in ultrasound data. This study develops a multi-spatiotemporal compounding CBE (MST-CBE) imaging approach for monitoring specific to CBUS thermal therapy.MethodsEx vivo thermal ablations were performed with stereotactic positioning of a 180° directional CBUS applicator, temperature monitoring probes, endorectal US probe, and subsequent lesion sectioning and measurement. Five frames of raw radiofrequency data were acquired throughout in 15s intervals. Using window-by-window estimation methods, absolute and positive components of MST-CBE images at each point were obtained by the compounding ratio of squared envelope data within an increasing spatial size in each short-time window.ResultsCompared with conventional US, Nakagami, and CBE imaging, the detection contrast and robustness quantified by tissue-modification-ratio improved by 37.2 ± 4.7 (p < 0.001), 37.5 ± 5.2 (p < 0.001), and 6.4 ± 4.0 dB (p < 0.05) in the MST-CBE imaging, respectively. Correlation coefficient and bias between cross-sectional dimensions of the ablation zones measured in tissue sections and estimated from MST-CBE were up to 0.91 (p < 0.001) and -0.02 mm2, respectively.ConclusionThe MST-CBE approach can monitor the detailed changes within target tissues and effectively characterize the dimensions of the ablation zone during CBUS energy deposition.SignificanceThe MST-CBE approach could be practical for improved accuracy and contrast of monitoring and evaluation for CBUS thermal therapy.

Background: Due to the anatomical complexity of the root canal system, irrigation plays an essential role in endodontics. This in vitrostudy was sought to compare the removal of the smear layer (RSL) promoted by conventional irrigation (CI), passive ultrasonic irrigation (PUI) and continuous ultrasonic irrigation (CUI) with 17% EDTA, by using scanning electron microscopy (SEM). Material and Methods: Forty single-rooted human mandibular canines were instrumented and randomly assigned to four groups (n=10), according to the irrigation protocol aiming to the RSL: CG (control group) —conventional irrigation with distilled water; CI— conventional irrigation with 17% EDTA; PUI —passive ultrasonic irrigation with 17% EDTA; CUI— continuous ultrasonic irrigation with 17% EDTA. Hemisections from each sample were obtained, and images of each root canal third (cervical, middle and apical) were captured at 1000 X magnification by SEM. Three previously calibrated and blinded evaluators classified the RSL, according to the criteria proposed by Torabinejad et al.: small or no smear layer (all dentinal tubules were clean and open); 2 = moderate smear layer (no smear layer on the surface of root canal, but dentinal tubules contained debris); 3 = dense smear layer (covering practically all dentinal tubules entrances). Statistical analysis was performed by Kruskal-Wallis and Bonferroni tests (p<0.05). Results: Overall, CUI and cervical thirds showed better RSL rates, compared with the other methods and thirds, respectively (p<0.05). More specifically, the cervical thirds showed better results in the CG, CI and PUI groups (p<0.05), whereas the cervical and middle thirds were not significantly different in the CUI group. Conclusion: CUI was the most effective method for the RSL., Antecedentes: Debido a la complejidad anatómica del sistema de conductos radiculares, la irrigación juega un papel fundamental en la endodoncia. Este estudio in vitro se buscó comparar la remoción de la capa de barro dentinario (RCBD) promovida por irrigación convencional (IC), irrigación ultrasónica pasiva (IUP) e irrigación ultrasónica continua (IUC) con EDTA al 17%, mediante el uso de microscopía electrónica de barrido (SEM). Material y Métodos:Se instrumentaron cuarenta caninos mandibulares humanos de raíz única y se asignaron aleatoriamente a cuatro grupos (n = 10), de acuerdo con el protocolo de riego apuntando a la RCBD: CG (grupo control) —riego convencional con agua destilada; IC— irrigación convencional con 17% de EDTA; IUP: irrigación ultrasónica pasiva con 17% de EDTA; IUC: irrigación ultrasónica continua con 17% de EDTA . Se obtuvieron hemisecciones de cada muestra y se capturaron imágenes de cada tercio del conducto radicular (cervical, medio y apical) con un aumento de 10 0 0X mediante SEM. Tres evaluadores previamente calibrados y ciegos clasificaron la RCBD, según los criterios propuestos por Torabinejad et al.: capa de frotis pequeña o nula (todos los túbulos dentinarios estaban limpios y abiertos); 2 = capa de frotis moderada (sin capa de frotis en la superficie del conducto radicular, pero los túbulos dentinarios contenían residuos); 3 = capa de frotis densa (que cubre prácticamente todas las entradas de los túbulos dentinarios). El análisis estadístico se realizó mediante las pruebas de Kruskal-Wallis y Bonferroni (p<0,05). Resultados: En general, IUC y tercios cervicales mostraron mejores tasas de RCBD, en comparación con los otros métodos y tercios, respectivamente (p<0,05). Más específicamente, los tercios cervicales mostraron mejores resultados en los grupos GC, IC y IUP (p<0,05), mientras que los tercios cervical y medio no fueron significativamente diferentes en el grupo IUC. Conclusión: CUI fue el método más eficaz para la RCBD.

Earthen architecture is one of the most relevant building technologies among heritage structures. However, mechanical properties are commonly obtained from destructive tests. To contribute at changing this trend, two non-destructive mechanical techniques (ultrasound and modal analysis) are studied to determine their ability at characterizing earthen materials and their possible correlation. To achieve these purposes, twenty cubic-shaped earthen specimens were produced for testing the capability of ultrasound transmission method to control moisture content and its evolution during drying process at different environments. Additionally, a real-scale rammed earth wall was built to assess the feasibility of using ultrasound technique to determine elastic dynamic Young modulus. This analysis was validated by indirect comparison with experimental modal analysis test results. The most important findings are that the relationship between moisture content and ultrasound transmission speed is linear. This information is useful to control the drying process of earthen materials and to control the moisture content distribution on larger in-service structures. Finally, numerical simulation using ultrasound transmission data as input information allow to predict the vibrational response of the tested wall with an error around 3%., Peer Reviewed, Postprint (published version)

The outer cortical table of the parietal bone has been commonly used as a calvarial bone graft site for the craniofacial reconstruction. However, little is known about how removing the outer table may affect the function and structure of the inner table, and how the knowledge of the biomechanics and material properties of cortical bones will help the calvarial graft to better integrate into the biological and mechanical functions of its surrounding native tissues. In this study, it was hypothesized that there were significant differences in both density and material properties between inner and outer cortical plates in cranial bones. Twelve cylindrical specimens, including inner-outer layers, of cortical parietal bone of a female baboon were collected. Cortical thicknesses and densities were measured, and elastic properties were assessed using an ultrasonic technique. Results demonstrated remarkable difference in both thickness (t = 8.248, p .0.05) and density (t = 4.926, p.0.05) between inner and outer cortical paired samples. Orthotropic characteristics of the cortical plates were detected as well, these findings suggest that there are differences in biomechanical properties between two surfaces of cranial bones at both tissue and organ levels. How these differences are linked to the stress environments of the inner and outer cranial cortical layers awaits further studies. Further study will greatly enhance our ability to address questions derived from both morphological and craniofacial medicine fields about the development and biomechanics of craniofacial skeletons. © 2020 Zapata, Wang.

The outer cortical table of the parietal bone has been commonly used as a calvarial bone graft site for the craniofacial reconstruction. However, little is known about how removing the outer table may affect the function and structure of the inner table, and how the knowledge of the biomechanics and material properties of cortical bones will help the calvarial graft to better integrate into the biological and mechanical functions of its surrounding native tissues. In this study, it was hypothesized that there were significant differences in both density and material properties between inner and outer cortical plates in cranial bones. Twelve cylindrical specimens, including inner-outer layers, of cortical parietal bone of a female baboon were collected. Cortical thicknesses and densities were measured, and elastic properties were assessed using an ultrasonic technique. Results demonstrated remarkable difference in both thickness (t = 8.248, p .0.05) and density (t = 4.926, p.0.05) between inner and outer cortical paired samples. Orthotropic characteristics of the cortical plates were detected as well, these findings suggest that there are differences in biomechanical properties between two surfaces of cranial bones at both tissue and organ levels. How these differences are linked to the stress environments of the inner and outer cranial cortical layers awaits further studies. Further study will greatly enhance our ability to address questions derived from both morphological and craniofacial medicine fields about the development and biomechanics of craniofacial skeletons. © 2020 Zapata, Wang.

Les lents de contacte (LC) són dispositius mèdics àmpliament utilitzats per a la correcció visual o per raons cosmètiques o terapèutiques. Tot i això, les LC són un factor en la predisposició a tenir infeccions oculars difícils de tractar com poden ser la queratitis microbiana i l’úlcera perifèrica, les quals poden causar deficiència visual i fins i tot ceguesa. Els principals factors en aquestes infeccions són l’adhesió bacteriana i la formació de biofilms a la superfície de les LC degut a la resistència de les cèl·lules sèssils als antibiòtics convencionals. En virtut d’això, hi ha una necessitat urgent de desenvolupar unes noves superfícies antibacterianes i antibiofilm per a LC que siguin capaces de prevenir les infeccions bacterianes oculars. En aquest estudi, nanopartícules bimetàl·liques de plata/or (AgAuNPs) i gelatina modificada amb DOPA sintetitzades mitjançant mètodes amb “química verda” s’han utilitzat per a dissenyar nous nanocompostos amb diferents mètodes d’acció per a minimitzar les infeccions bacterianes relacionades amb LC mitjançant un procés ultrasonoquímic d’un sol pas. El recobriment híbrid desenvolupat va portar a un augment de la humectabilitat del material de silicona i va demostrar una gran capacitat per impedir als bacteris Staphylococcus aureus i Pseudomona aeruginosa la formació del biofilm en un 80% i 60% respectivament. Els nous recobriments nano-actius tenen un gran potencial per eliminar els patògens en humans, sense afectar a la viabilitat ni a la morfologia de les cèl·lules dels mamífers convertint-se en una estratègia molt prometedora per a la prevenció d’infeccions bacterianes relacionades amb les LC., Las lentes de contacto (LC) son dispositivos médicos ampliamente utilizados para la corrección visual y para fines cosméticos o terapéuticos. Sin embargo, las LC son un factor en la predisposición a tener infecciones oculares difíciles de tratar como pueden ser la queratitis microbiana y la úlcera periférica, las cuales pueden causar deficiencia visual e incluso ceguera. Los principales factores en estas infecciones son la adhesión bacteriana y la formación de biofilm en la superficie de las LC debido a la resistencia de las células sésiles a los antibióticos convencionales. En virtud de ello, hay una necesidad urgente de desarrollar unas nuevas superficies antibacterianas y antibiofilm para LC que sean capaces de prevenir las infecciones bacterianas oculares. En este estudio, nanopartículas bimetálicas de plata/oro (AgAuNPs) y gelatina modificada con DOPA sintetizadas mediante métodos con “química verde” se han utilizado para diseñar nuevos nanocompuestos con diferentes métodos de acción para minimizar las infecciones bacterianas relacionadas con las LC mediante un proceso ultraosonoquímico de un solo paso. El recubrimiento híbrido desarrollado llevó a una augmento de la humectabilidad del material de silicona y demostró una gran capacidad para impedir a las bacterias Staphylococcus aureus y Pseudomona aeruginosa la formación del biofilm en un 80% y 60% respectivamente. Los nuevos recubrimientos nano-activos tienen un gran potencial para eliminar a los patógenos en humanos, sin afectar a la viabilidad ni a la morfología de las células de los mamíferos convirtiéndose en una estrategia muy prometedora para la prevención de infecciones bacterianas relacionadas con las LC., The contact lenses (CLs) are widely used medical devices for visual correction or therapeutic and cosmetic reasons. However, the CLs are a predisposing factor for difficult-to-treat ocular infections such as microbial keratitis and peripheral ulcer, which can cause visual impairment and blindness. The main significant impact on these infections is the bacterial adhesion and biofilm formation on the CLs surfaces due to drug resistance of the sessile cells to the conventional antibiotics. In this line, there is an urgent need for development of novel antibacterial and antibiofilm CLs surfaces for prevention of ocular bacterial infections. Herein, in the present work, green synthetized bimetallic silver/gold nanoparticles (AgAu NPs) and dopamine-modified gelatin have been employed for engineering of novel nanostructured composites with complimentary modes of action to minimize the CLs-associated infections occurrence in a one-step high-intensity sonochemical process. The developed hybrid coating led to enhanced wettability of the silicone material and demonstrated very strong capacity to impede the Staphylococcus aureus and the Pseudomonas aeruginosa biofilm formation by 80% and 60% respectively. The novel nano-enabled coatings had a great potential to eliminate the human pathogens, without affecting the mammalian cells viability and morphology, showing to be a promising strategy for prevention of CL-related bacterial infections.

La industria del automóvil crece año tras año de manera muy rápida, y por ello, todos los que la integran deben estar a la vanguardia en todo lo que ello conlleva para poder ser competitivos. Este proyecto nace de la evolución de un sensor electrónico de una importante marca de recambios de automoción, el cual tiene la necesidad de migrar de tecnología para seguir siendo competitivo en el mercado y a su vez mejorar en todos los aspectos de calidad. El objetivo de este proyecto es el de implementar y adaptar la soldadura por ultrasonidos en el proceso de fabricación de sensores diferenciales de presión de escape. Esto conlleva una migración de tecnología, rediseño de sensor y útiles para adaptar lo que actualmente se suelda con estaño a ultrasonido, mejorando ampliamente todos los factores que participan en el proceso de fabricación y del propio producto. El proyecto incluye el rediseño del producto, los útiles necesarios para su proceso de fabricación, la programación de la máquina de ultrasonidos, la integración de la máquina a una línea automática, la homologación del producto final y su puesta en el mercado. Mencionar que el sensor se ha llevado con éxito en la realidad y se ha desarrollado este proyecto de manera paralela plasmando todo lo necesario para llevarlo a cabo., The automotive industry grows year after year very quickly, and therefore, all those who make it up must be at the forefront in all that this entails in order to be competitive. This project was born from the evolution of an electronic sensor from an important brand of automotive spare parts, which has the need to migrate technology to remain competitive in the market and to improve in all aspects of quality. The objective of this project is to implement and adapt ultrasonic welding in the manufacturing process of differential exhaust pressure sensors. This entails a migration of technology, sensor redesign and tools to adapt what is currently soldered with tin to ultrasound, greatly improving all the factors that participate in the manufacturing process and the product itself. The project includes the redesign of the product, the tools necessary for its manufacturing process, the programming of the ultrasound machine, the integration of the machine to an automatic line, the approval of the final product and its placing on the market. Mention that the sensor has been successfully carried out in reality and this project has been developed in a parallel way, capturing everything necessary to carry it out.

In this final degree thesis, a prototype of a system has been designed to assist in transcranial insonation research. The designed system is capable of generating three-level square waveforms to excite up to 8 (expandable to 16) channels of a multi-beam ultrasonic system to be used in transcranial insonation. These waveforms are burst of square signals that can be configured both in frequency and in the rest of the signal parameters, including the delays between channels, by means of a particular program. In this report are the needs and specifications to be accomplished, with the corresponding solutions adopted, each and every one of them with the most precise justifications on the validity of the same. It is due to these premises that there is an implicit visualization of the system in question, the necessary simulations and tests and, consequently, the final result obtained.