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Multi-mechanical waves against Alzheimer’s disease pathology:a systematic review

Translational Neurodegeneration 2021年第3期10卷 459-486页

作者： Francisca Monteiro Ioannis Sotiropoulos Óscar Carvalho Nuno Sousa Filipe S.Silva Center for Microelectromechanical Systems(CMEMS) University of MinhoCampus Azurém4800-058 GuimarãesPortugal Life and Health Sciences Research Institute(ICVS) Medical SchoolUniversity of MinhoCampus Gualtar4710-057 BragaPortugal ICVS/3B’s-PT Government Associate Laboratory Braga/GuimarãesPortugal Institute of Biosciences&Applications NCSR“Demokritos” AthensGreece

Alzheimer’s disease(AD)is the most common cause of dementia,afecting approximately 40 million people *** inefectiveness of the available pharmacological treatments against AD has fostered researchers to focus on alternative strategies to overcome this *** vibrations delivered in diferent stimulation modes have been associated with marked improvements in cognitive and physical performance in both demented and nondemented *** of the mechanical-based stimulation modalities in eforts are earlier whole-body vibration,transcranial ultrasound stimulation with microbubble injection,and more recently,auditory ***,there is a huge variety of treatment specifcations,and in many cases,conficting results are *** this review,a search on Scopus,PubMed,and Web of Science databases was performed,resulting in 37 *** studies suggest that mechanical vibrations delivered through diferent stimulation modes are efective in attenuating many parameters of AD pathology including functional connectivity and neuronal circuit integrity defcits in the brains of AD patients,as well as in subjects with cognitive decline and non-demented older *** the evolving preclinical and clinical evidence on these therapeutic modalities,their translation into clinical practice is not consolidated ***,this comprehensive and critical systematic review aims to address the most important gaps in the reviewed protocols and propose optimal regimens for future clinical application.

关键词： Alzheimer’s disease Auditory stimulation Mechanical vibrations ultrasounds Whole-body vibration

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Ultrasonic Sensors with Mechanical Couplers： Simulation and Validation

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Journal of Mathematics and System Science 2012年第4期2卷 264-271页

作者： Monica Femendez Cristina Rodriguez Juan M. Perez Oria Manuel Ibarra Luciano Alonso Department of Electronic Technology and Automatic Control Systems University of Cantabria Santander 39005 Spain

The use of ultrasonic sensors has varied applications, but the sensor operation frequency limits the operating distance. An easy way to increase this distance is to couple a mechanical element （horn）, but it is necessary to characterize this technique. In this paper the results obtained in a study of the behaviour of mechanical elements coupled to an ultrasonic sensor using finite element techniques are presented. These results have been obtained using Comsol Multiphysics modelling. Also, the effect caused by the sensor size on the radiation acoustic pressure has also been evaluated. In other way, in this paper it is presented the results obtained in the laboratory measurements. First, it is studied the influence of a straight horn attached to the ultrasonic sensor. Later, it is presented the variation in the sound pressure on the radiation axis when the sensor varies its size. In the final part of the paper, the experimental validation of the simulations is presented.

关键词： ultrasounds sensors homs radiation pattem.

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Determining the Thermal Conductivity in Walls of Cast Iron Castings by the Ultrasound Technique

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材料科学与工程（中英文A版） 2021年第4期11卷 120-128页

作者： Jerzy Stanisław Zych Marcin Myszka Krzysztof Piotrowski Faculty of Foundry Engineering AGH University of Science and TechnologyReymonta 23Cracow 30-059Poland Krakodlew S.A. Ujastek 130-969 CracowPoland

Research results concerning the application of ultrasound technique for determining the averaged thermal conductivity in walls of castings produced of cast iron(solidifying in a steady system)containing carbon precipitates in a graphite form,are presented in the hereby *** concern castings of unalloyed cast *** influence of the form of graphite precipitates on the cast iron thermal conductivity as well as on the propagation velocity of the ultrasound wave,including the longitudinal wave velocity CL,was investigated in the *** influence of the graphite form,described by the shape indicator(f),on the thermal conductivity(l)(determined on samples by the steady heat flow method)as well as the influence of this indicator(f)on the wave propagation velocity(CL),was investigated.A series of melts of cast iron,of the near eutectic chemical composition,were *** introduced in a wide range,allowed obtaining various graphite forms from flake,via mixed,vermicular to ***:l=f(CL),CL=f(f)were determined and at the final phase the empirical dependencel=f(CL)was also *** thermal conductivity and ultrasound wave velocity were tested on the same *** thermal conductivity coefficient of cast iron(l)was changing in a wide range from approximately 32 to 46 W/s·m,while the wave velocity CL respectively:from approximately 4,300 to 5,800 m/*** empirical dependencel=f(CL),determined in the described variability ranges,is of a linear character and the correlation level equals:R2=*** validation of the experimental results was performed on cast iron castings of slag ladles,since they are required to be of a good thermal *** possibility of assessing the thermal conductivity directly in walls of such castings by means of non-destructive ultrasound method,was *** real thermal conductivity determined in the walls of the castings is used to simulate the heating and cooling process of slag ladles

关键词： Thermal conductivity ultrasounds cast iron research tools.

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3D Localization and Tracking of Objects Using Miniature Microphones

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Wireless Sensor Network 2011年第5期3卷 147-157页

作者： Radu Ionescu Riccardo Carotenuto Fabio Urbani 不详

Asystemfor accurate localization and trackingof remote objects is introduced, which employs a reference frame of four coplanar ultrasound sources as transmitters and miniature microphones that equip the remote objects as receivers. The transmitters are forced to emit pulses in the 17 - 40 kHz band. A central processing unit, knowing the positions of the transmitters and the time of flight of the ultrasound signals until they reach the microphones, computes the positions of the microphones, identifying and discarding possible false signals due to echoes and environmental noise. Once the microphones are localized, the position of the object is computed by finding the placement of the geometrical reconstructed object that fitsbest with the calculated microphones positions. The operating principle of the localization system is based on successive frames. The data are processed in parallel for all the microphones that equip the remote objects, leading to a high repetition rate of localization frames. In the proposed prototype, all the computation, including signal filtering, time of flight detection, localization and results display, is carried out about 25 times per second on a notebook PC.

关键词： Localization System Remote Object Tracking ultrasounds Time of Flight

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Ultrasound Poroelastic Tissue Typing

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Open Journal of Acoustics 2011年第3期1卷 55-62页

作者： Piero Chiarelli Bruna Vinci Antonio Lanatà Valeria Gismondi Simone Chiarelli 不详

Employing the poroelastic theory of acoustic waves in gels, the ultrasound (US) propagation in a gel medium filled by poroelastic spherical cells is studied. The equation of fast compressional wave, the phase velocity and the attenuation as a function of the elasticity, porosity and concentration of the cells into the gel matrix are investigated. The outcomes of the theory agree with the preliminary measurements done on PVA gel scaffolds inseminated by porcine liver cells at various concentrations. The feasibility of a non-invasive technique for the health assessment of soft biological tissues steaming by the model is analyzed.

关键词： Ultrasound Bi-Phasic Model of Living Tissues Non-Invasive Ultrasound Assessment Poroelastic ultrasounds in Soft Tissues

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Echography in brain imaging in intensive care unit: State of the art

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World Journal of Radiology 2014年第9期6卷 636-642页

作者： Anselmo Caricato Sara Pitoni Luca Montini Maria Grazia Bocci Pina Annetta Massimo Antonelli Department of Anes-thesiology and Intensive Care Medicine Catholic University of the Sacred Heart "A. Gemelli" Teaching Hospital Intensive Care Unit

Transcranial sonography(TCS)is an ultrasound-based imaging technique,which allows the identification of several structures within the brain *** the past it has been applied for bedside assessment of different intracranial pathologies in ***-ently,TCS is also used on adult patients to diagnose intracranial space occupying lesions of various origins,intracranial hemorrhage,hydrocephalus,midline shift and neurodegenerative movement disorders,in both acute and chronic clinical *** comparison with conventional neuroimaging methods(such as com-puted tomography or magnetic resonance),TCS has the advantages of low costs,short investigation times,repeatability,and bedside *** noninva-sive characteristics,together with the possibility of of-fering a continuous patient neuro-monitoring system,determine its applicability in the monitoring of multiple emergency and non-emergency ***,TCS is a still underestimated imaging modality that requires a wider diffusion and a qualified training *** this review we focused on the main indications of TCSfor the assessment of acute neurologic disorders in in-tensive care unit.

关键词： Brain sonography Transcranial sonography ultrasounds Cerebral sonography Brain imaging Hy-drocephalus Cerebral hemorrhage

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Rose Essential Oil Extraction from Fresh Petals Using Synergetic Microwave ＆ Ultrasound Energy： Chemical Composition and Antioxidant Activity Assessment

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Journal of Chemistry and Chemical Engineering 2016年第3期10卷 136-142页

作者： Mariana Patrascu Marilena Radoiu R&D Department Sintchem Technologies Ltd Codlea Brasov Romania R&D Department ChemspeedLtd. Bucharest Romania

The aim of the present work was to investigate the synergetic effect of microwave and ultrasound treatment on the production, chemical composition and antioxidant activity of rose essential oil. The rose essential oil was extracted from fresh Rosa x damciscena Mill. petals by four methods, hydrodistillation, steam distillation, organic solvent extraction and ultrasounds followed by microwave hydrodistillation. The chemical composition of the extracts was analysed by GC-MS, and the antioxidant capacity by DPPH. It was found that both chemical composition and the antioxidant activity of the extracts depend on the extraction method. Overall it was found that microwaves coupled with ultrasonic treatment can be used effectively for the intensification of the extraction of monoterpenes and sesquiterpenes--fragrance bearing molecules--and equally, for increased antioxidant activity while using about 4 time shorter extraction time. The scale-up of the method was also evaluated. The results obtained in this research support the possible use of the US/MW method for the extraction of rose essential oil for the pharmaceutical and fragrance industry.

关键词： 2.45 GHz microwaves ultrasounds rose petals essential oil scale-up hydrodistillation.

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The Effect of Micro-Pulsatile Electrical and Ultrasound Stimulation on Cellular Biosynthetic Activities Such as Cellular Proliferation, Endogenous Nitrogen Oxide and Collagen Synthesis

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Journal of Cosmetics, Dermatological Sciences and Applications 2016年第1期6卷 41-47页

作者： Doris-Antoinette Mbeh Insaf Hadjab Mihaela-Elena Ungur L’Hocine Yahia Laboratory of Innovation and Analysis of Bioperformance (LIAB) Mechanical/Biomedical Engineering Department Polytechnique Montréal Montreal Canada

The skin barrier poses an ongoing challenge for the cosmetics industry. Its penetration, by non-invasive means, can readily be achieved with currents and ultrasound or radiofrequency devices through electroporation, sonophoresis, iontophoresis or cavitation. When several types of energy are applied simultaneously, we expect the effects to be magnified and all the more effective. Although the mechanism of action of each technology on the skin is not entirely controlled, and is even less so when multiple technologies are applied concurrently, some studies demonstrate that nitric oxide (NO) plays a pivotal role in skin wound-healing and regeneration. With regard to wound healing, one of the key functions of NO appears to be its permissive effect on keratinocyte and fibroblast proliferation, which helps promote wound re-epithelialization. The objective of the actual research is to gain an in-depth understanding of the mechanisms generated by NO through the application of a specific combination of technologies.

关键词： Collagen Fibroblasts NO Aesthetic Technologies ultrasounds Electric Current

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