A5034211767- Ultrasound Imaging and Elastography
- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Ultrasonics and Acoustic Wave Propagation
- Infrared Thermography in Medicine
- Bone health and osteoporosis research
- Bone fractures and treatments
- Electronic and Structural Properties of Oxides
- Electrical and Bioimpedance Tomography
- Radiation Dose and Imaging
- Ultrasound in Clinical Applications
- Cardiovascular Health and Disease Prevention
- Engineering Applied Research
- Flow Measurement and Analysis
- Advanced MRI Techniques and Applications
- Optical Imaging and Spectroscopy Techniques
- Hemodynamic Monitoring and Therapy
- Non-Invasive Vital Sign Monitoring
- AI in cancer detection
- Grouting, Rheology, and Soil Mechanics
- Breast Lesions and Carcinomas
- Advanced Photocatalysis Techniques
- Cardiac Imaging and Diagnostics
- Wireless Body Area Networks
- Non-Destructive Testing Techniques
Bauhaus-Universität Weimar
2018-2025
Universidade Federal do Rio de Janeiro
2013-2024
Universität Hamburg
2023-2024
Hamburg Institut (Germany)
2024
Otto-von-Guericke University Magdeburg
2018
University of Coimbra
2012
Instituto Nacional de Metrologia, Qualidade e Tecnologia
2012
Ruhr University Bochum
2003
University of Leicester
2002
CuBi2 O4 has recently emerged as a promising photocathode for photo-electrochemical (PEC) water splitting. However, its fast degradation under operation currently poses limit to application. Here, we report novel method study operando the semiconductor-electrolyte interface during PEC by surface-sensitive high-energy X-ray scattering. We find that decrease in generated photocurrents correlates directly with formation of metallic Bi phase. further show slower Cu, well dissolution electrode...
Abstract Die Entwicklung von neuartigen Lehmsteinen, Plansteinen und Planelementen samt dazu passendem Mörtel ist in den vergangenen Jahren rasant gestiegen. Neue Materialen Systeme verlangen aber auch nach neuen Prüfmethoden ein fundiertes Verständnis für das Materialverhalten. 2D‐Verformungsmessung ermöglicht es die Verformungen der Prüfkörper zu jedem Zeitpunkt Prüfung betrachten. Untersucht wurde Druckfestigkeit drei RILEM‐Prüfkörper aus Lehmsteinen mit Dünnbettmörtel Dickbettmörtel bei...
Ultrasound (US) phantoms are made of materials that mimic acoustic properties human soft tissue. Ideally, such should US velocity (1435 to 1631 m.s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ), attenuation (0.22 1.47 dB.cm MHz xmlns:xlink="http://www.w3.org/1999/xlink">-n</sup> with ranging from 1.09 1.15), density (916 1100 kg.m xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> ) and scattering. Many the tested have some desired...
An Optical Frequency Domain Reflectometry (OFDR) based fiber optic sensor scheme "embedded" in concrete for the purpose of structural health monitoring (SHM) carbon composites (C³) is presented. The design, while strengthening structure, also aims to monitor common SHM parameters such as strain and cracks. This was achieved by weaving together with optical fiber, on a specialized technique that uses an embroidery setup where both are woven water dissolvable polymer substrate. performance...
A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses Wistar rats in vivo. Five [apparent integrated backscatter (AIB), frequency slope apparent (FSAB), time (TSAB), reflection coefficient (IRC), and (FSIR)] were calculated using echoes from cortical trabecular bone femurs 14 rats. Signal acquisition performed three times each rat, with signal acquired along femur's central region...
Abstract Bone mineral density is an important parameter for the diagnosis of bone diseases, as well predicting fractures and treatment monitoring. Thus, aim present study was to evaluate potential Quantitative Ultrasound (QUS) monitor changes after calcium, phosphorus, magnesium loss in rat femurs vitro during a demineralization process. Four quantitative ultrasound parameters were estimated from surface echoes eight femur diaphysis rats. The echo signals acquired decalcification process by...
Abstract Ultrasound (US) phantoms are used to simulate the main acoustic properties of human soft tissues and usually applied in guided biopsy training equipment calibration. In this work it is presented an ultrasound phantom that mimics breast lesions with irregular edge, which a typical feature related malignancy. The matrix was made mixture water, agar, glycerine graphite PVC powders were silicon polyacrylamide. mimicking US attenuation, propagation speed density. images obtained visually...
Crosstalk is a result of the deficiency in electrical or mechanical isolation between elements. It function proximity piezoelectric elements transducer connections. can be caused by series factors, such as: electromagnetic shield, capacitive effect connections, transmission vibration modes to adjacent due insufficient isolation. also depends on geometry and connecting material The evaluation crosstalk effects matrix ultrasonic transducers presented. Measurement methods radiation patterns...
Biological phantoms are very useful for controlled experiments on biomedical ultrasound. Nevertheless they normally made of materials with short time-duration (organic materials). We have been studying the ultrasonic properties test-blocks polyvinyl chloride-plastisol (PVCP) that stable in time. In this work we analyzed (US) attenuation and speed at 1MHz, as a function temperature (20 to 40°C) four PVCP different concentrations graphite powder cooking temperature, using classical US...
A novel digital instrument has been developed for loss-factor measurement. It is program controlled, easy to operate, and a measurement resolution of tan delta -0.1 Hz=0.01%. The loss angle determined by range crossovers current voltage. At 0.1 Hz considerably larger dynamic than at 50 Hz; this reason especially suitable diagnostics the operational efficiency plastic cables. Measurements on naturally aged cables showed that there definite correlation between increased reduced breakdown...
Resumo O presente trabalho descreve o projeto e construção de um calorímetro diferencial com a finalidade avaliar aquecimento gerado por feixes ultrassônicos em níveis terapêuticos.O consiste duas câmaras cilíndricas alumínio idênticas (de medição referência), preenchidas material mimetizador tecido biológico (phantom).Cada câmara possui seis termopares tipo E (diâmetro 0,24 mm), posicionados ao longo do eixo central propagação da onda, entre as profundidades 10-60 mm, distantes 10 mm si.Foi...
Abstract Background and Objective The improvement in the appearance of skin with dermal striae (DS) is currently eval‐uated by invasive methods, such as biopsy. This study evaluates whether high‐resolution ultrasound (HRUS) could be used to identify lesions vivo caused DS, using 2D images measuring thickness layer. Methods High‐resolution at frequencies 20 30 MHz was this ten volunteers DS. layers estimated tracing five vertical lines from epidermis (EP) dermis (DE) DE hypodermis (H)...
One goal of therapeutic ultrasound is enabling heat generation in tissue. Ultrasound application protocols typically neglect these processes absorption and backscatter/reflection at the skin/fat, fat/muscle, muscle/bone interfaces. The aim this study was to investigate heating process interfaces close transducer bone with aid computer simulation tissue-mimicking materials (phantoms). experimental setup consists physiotherapeutic equipment for irradiation, two layers soft material, one...
We describe the concept of a new imaging modality based on tracking and dynamic modeling local intensity changes (ICs) observed in conventional ultrasound images collected during medium-temperature change. computed pixel-by-pixel IC from averaged B-mode that exhibited different behaviors with varying temperature resulting speed sound, which consequently induce backscattered energy. Moreover, for each pixel, first-order polynomial model was adjusted to temperature-dependent ICs. The...
Introduction: Ultrasound Transit-Time flowmeters are based on the fact that time required for an ultrasound pulse to propagate through a given distance in moving medium is function of vectorial sum propagation velocity and velocity.The most common application this flowmeter medicine evaluation blood flow arteries veins during heart vascular surgery.The present article describes design, construction phantom transit-time calibration.Methods: Basically, it hydraulic circuit containing degassed...
Introduction Therapeutic ultrasound (TUS) is a widespread modality in physiotherapy, and the water bag technique coupling method employed presence of anatomical irregularities treatment area. The aim present study to evaluate acoustic attenuation its effectiveness as TUS agent. Methods rated output powers (ROPs) equipment were evaluated based on IEC 61689. Then, radiation force balance was used measure ROP with without (latex nitrile gloves filled deionized water) between transducer...
Low-intensity physiotherapeutic ultrasound has been used in physical therapy clinics; however, there remain some scientific issues regarding the bone-healing process. The objective of this study was to investigate influence low-intensity on initial stage bone healing rats. Twenty-two male adult rats were assessed quantitatively and qualitatively using radiographic, biochemical, histological analyses. Numerical simulations also performed. Fractures animals group (n = 11) treated with (pulsed...