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1.
Nano Lett ; 24(21): 6362-6368, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38752764

ABSTRACT

Plasmonic nanoantennas have proven to be efficient transducers of electromagnetic to mechanical energy and vice versa. The sudden thermal expansion of these structures after an ultrafast optical pulsed excitation leads to the emission of hypersonic acoustic waves to the supporting substrate, which can be detected by another antenna that acts as a high-sensitivity mechanical probe due to the strong modulation of its optical response. Here, we propose and experimentally demonstrate a nanoscale acoustic lens comprised of 11 gold nanodisks whose collective oscillation at gigahertz frequencies gives rise to an interference pattern that results in a diffraction-limited surface acoustic beam of about 340 nm width, with an amplitude contrast of 60%. Via spatially decoupled pump-probe experiments, we were able to map the radiated acoustic energy in the proximity of the focal area, obtaining a very good agreement with the continuum elastic theory.

2.
Sensors (Basel) ; 21(8)2021 Apr 12.
Article in English | MEDLINE | ID: mdl-33921505

ABSTRACT

This work illustrates the analysis of Film Bulk Acoustic Resonators (FBAR) using 3D Finite Element (FEM) simulations with the software OnScale in order to predict and improve resonator performance and quality before manufacturing. This kind of analysis minimizes manufacturing cycles by reducing design time with 3D simulations running on High-Performance Computing (HPC) cloud services. It also enables the identification of manufacturing effects on device performance. The simulation results are compared and validated with a manufactured FBAR device, previously reported, to further highlight the usefulness and advantages of the 3D simulations-based design process. In the 3D simulation results, some analysis challenges, like boundary condition definitions, mesh tuning, loss source tracing, and device quality estimations, were studied. Hence, it is possible to highlight that modern FEM solvers, like OnScale enable unprecedented FBAR analysis and design optimization.

3.
Biosensors (Basel) ; 9(1)2018 Dec 26.
Article in English | MEDLINE | ID: mdl-30587840

ABSTRACT

In the present work, a novel, portable and innovative eNose composed of a surface acoustic wave (SAW) sensor array based on zeolitic imidazolate frameworks, ZIF-8 and ZIF-67 nanocrystals (pure and combined with gold nanoparticles), as sensitive layers has been tested as a non-invasive system to detect different disease markers, such as acetone, ethanol and ammonia, related to the diagnosis and control of diabetes mellitus through exhaled breath. The sensors have been prepared by spin coating, achieving continuous sensitive layers at the surface of the SAW device. Low concentrations (5 ppm, 10 ppm and 25 ppm) of the marker analytes were measured, obtaining high sensitivities, good reproducibility, short time response and fast signal recovery.


Subject(s)
Breath Tests , Diabetes Mellitus/diagnosis , Diabetes Mellitus/metabolism , Electronic Nose , Nanoparticles/chemistry , Sound , Zeolites/chemistry , Acetone/analysis , Ammonia/analysis , Biomarkers/analysis , Ethanol/analysis , Humans , Sensitivity and Specificity , Surface Properties
4.
Sensors (Basel) ; 17(11)2017 Nov 14.
Article in English | MEDLINE | ID: mdl-29135919

ABSTRACT

Love-wave gas sensors based on surface functionalized iron oxide nanoparticles has been developed in this research. Amino-terminated iron oxide nanoparticles were deposited, by a spin coating technique, onto the surface of Love-wave sensors, as a very reproducible gas-sensing layer. The gases tested were organic solvents, such as butanol, isopropanol, toluene and xylene, for a wide and low concentration range, obtaining great responses, fast response times of a few minutes (the time at which the device produced a signal change equal to 90%), good reproducibilities, and different responses for each detected solvent. The estimated limits of detection obtained have been very low for each detected compound, about 1 ppm for butanol, 12 ppm for isopropanol, 3 ppm for toluene and 0.5 ppm for xylene. Therefore, it is demonstrated that this type of acoustic wave sensor, with surface amino-functionalized nanoparticles, is a good alternative to those ones functionalized with metal nanoparticles, which result very expensive sensors to achieve worse results.

5.
J Cosmet Laser Ther ; 19(6): 314-319, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28590827

ABSTRACT

Extracorporeal Shockwave Therapy (ESWT) has had a wide use in rehabilitation, and has presented positive effects in the treatment of unaesthetic affections. The objective of the present study was to search, in the literature, the mechanisms of action and the physiological aspects of shockwaves acting on the biological tissue to improve the condition of cellulite and localized fat. The systematic review of the literature was carried out in the period of September 2016 to February 2017 based on the bibliographic databases such as Lilacs, Medline, PubMed, and SciELO. Fifteen articles were identified in that systematic review, three of which were excluded as they did not make the complete access to the article available or the theme investigated did not encompass the objective of the study. The revision demonstrated that extracorporeal shockwaves present relevant effects on the biological tissue, which leads to the restructuring of skin properties and subcutaneous tissue, thus clinically improving the aspects of cellulite and localized fat.


Subject(s)
Adipose Tissue , Cellulite/therapy , Cosmetic Techniques , High-Energy Shock Waves/therapeutic use , Humans , Subcutaneous Fat
6.
J Cosmet Laser Ther ; 19(3): 165-173, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27997260

ABSTRACT

BACKGROUND: Cellulite is a common aesthetic condition that affects almost every woman. OBJECTIVE: To evaluate the efficacy of acoustic wave therapy (AWT) for cellulite and body shaping. METHODS: In this open-label, single-centre trial, 30 women presenting moderate or severe cellulite underwent 12 sessions of AWT on the gluteus and back of the thighs, over six weeks. The following assessments were performed at baseline, and up to 12 weeks after treatment: Cellulite Severity Scale (CSS), body circumference measurements, subcutaneous fat thickness by magnetic resonance imaging (MRI), quality of life related by Celluqol® and a satisfaction questionnaire. RESULTS: The treatment reduced cellulite severity from baseline up to 12 weeks after the last treatment session (subjects presenting severe cellulite: 60% to 38%). The mean CSS shifted from 11.1 to 9.5 (p < 0.001). Hips circumferences reduced from 99.7 and 103.2 cm to 96.2 and 100.3 cm (respectively, p < 0.001). The average thickness of the subcutaneous fat tissue also decreased (28.3 ± 6.5 mm to 26.7 ± 6.1mm; p < 0.001). The treatment also improved quality of life. More than 90% of the subjects would undergo the treatment again and 89% were satisfied with the results. No serious adverse events were reported. CONCLUSIONS: AWT is a safe treatment to improve cellulite appearance and reduce body circumferences.


Subject(s)
Body Contouring/methods , Cellulite/radiotherapy , Sound , Subcutaneous Fat/radiation effects , Adult , Body Weights and Measures , Buttocks , Female , Hip/anatomy & histology , Humans , Magnetic Resonance Imaging , Middle Aged , Patient Satisfaction , Prospective Studies , Quality of Life , Severity of Illness Index , Subcutaneous Fat/diagnostic imaging , Subcutaneous Fat/pathology , Surveys and Questionnaires , Thigh
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