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1.
Bioelectrochemistry ; 158: 108708, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38636366

RESUMEN

Ca2+, in combination with SP or EP, induces cell cytotoxicity much faster compared to BLM. The application of BLM in combination with, SP or EP, reaches the level of cell death, induced by similar combination with Ca2+, only after 72 h. The methods of SP and EP were calibrated according to the level of differential cytotoxicity, determined after 6 days (using cell clonogenic assay). The combination of Ca2+ SP induces cell death faster than Ca2+ EP - after Ca2+ SP it increases to a maximum level after 15 min and remains constant for up to 6 days, while the cytotoxic efficiency after Ca2+ EP increases to the level of Ca2+ SP only after 72 h. The combination of BLM SP shows a very similar dynamics to BLM EP - both reach maximal level of cytotoxicity after 48-72 h. Ca2+ and BLM in combination with SP have shown similar levels of cytotoxicity at higher acoustic pressures (≥250 kPa); therefore, Ca2+ SP can be used to induce immediate and maximal level of cytotoxic effect. The faster cytotoxic efficiency of Ca2+ in combination with SP than EP was determined to be due to the involvement of microbubble inertial cavitation.


Asunto(s)
Bleomicina , Calcio , Electroporación , Calcio/metabolismo , Electroporación/métodos , Bleomicina/farmacología , Humanos , Supervivencia Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Línea Celular Tumoral
2.
Sensors (Basel) ; 24(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38543981

RESUMEN

Multilayer printed circuit boards (PCBs) can be produced not only in the traditional way but also additively. Both traditional and additive manufacturing can lead to invisible defects in the internal structure of the electronic component, eventually leading to the spontaneous failure of the device. No matter what kind of technology is used for the production of PCBs, when they are used in important structures, quality control is important to ensure the reliability of the component. The nondestructive testing (NDT) of the structure of manufactured electronic components can help ensure the quality of devices. Investigations of possible changes in the structure of the product can help identify the causes of defects. Different types of manufacturing technologies can lead to diverse types of possible defects. Therefore, employing several nondestructive inspection techniques could be preferable for the inspection of electronic components. In this article, we present a comparison of various NDT techniques for the evaluation of the quality of PCBs produced using traditional and additive manufacturing technologies. The methodology for investigating the internal structure of PCBs is based on several of the most reliable and widely used technologies, namely, acoustic microscopy, active thermography, and radiography. All of the technologies investigated have their advantages and disadvantages, so if high-reliability products are to be produced, it would be advantageous to carry out tests using multiple technologies in order to detect the various types of defects and determine their parameters.

3.
Materials (Basel) ; 16(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38068134

RESUMEN

In guided-wave-based damage-imaging algorithms, damage reconstruction typically involves comparing the signals with and without a defect. However, in many cases, defect-free data may not be available. Therefore, in this study, baseline and baseline-free approaches were used for damage imaging, exploiting not only the amplitude of the signal as the feature but also five additional features, namely, the amplitude of the sparse signal after deconvolution, the amplitude of the coefficients at the excitation frequency from the re-assigned short-time Fourier transform, the time of flight determined from cross-correlation, kurtosis in the time domain, and kurtosis in the frequency domain. For this study, three different plates with different types of defects were considered: a metallic plate with a notch-type artificial defect, a pultruded type of composite plate with an impact defect, and a laminate composite plate with plexiglass serving as an added mass damper artificial defect. The Reconstruction Algorithm for Probabilistic Inspection of Damage (the RAPID algorithm) was used to characterize the defects on the three plates, and the defect parameters were then quantified by creating an ellipse after thresholding.

4.
Sensors (Basel) ; 23(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38005438

RESUMEN

This paper presents a baseline-free damage imaging technique using a parallel array of piezoelectric sensors and a control board that facilitates custom combinations of sensor selection. This technique incorporates an imaging algorithm that uses parallel beams for generation and reception of ultrasonic guided waves in a pitch-catch configuration. A baseline-free reconstruction algorithm for probabilistic inspection of defects (RAPID) algorithm is adopted. The proposed RAPID method replaces the conventional approach of using signal difference coefficients with the maximum signal envelope as a damage index, ensuring independence from baseline data. Additionally, conversely to the conventional RAPID algorithm which uses all possible sensor combinations, an innovative selection of combinations is proposed to mitigate attenuation effects. The proposed method is designed for the inspection of lap joints. Experimental measurements were carried out on a composite lap joint, which featured two dissimilar-sized disbonds positioned at the lap joint's borderline. A 2D correlation coefficient was used to quantitatively determine the similarity between the obtained images and a reference image with correct defect shapes and locations. The results demonstrate the effectiveness of the proposed damage imaging method in detecting both defects. Additionally, parametric studies were conducted to illustrate how various parameters influence the accuracy of the obtained imaging results.

5.
Materials (Basel) ; 16(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37895746

RESUMEN

The integrity of delaminated composite structures can be restored by introducing a thermally-based healing effect on continuous fiber-reinforced thermoplastic composites (CFRTPC). The phenomenon of thermoplastics retaining their properties after melting and consolidation has been applied by heating the delaminated composite plates above their glass transition temperature under pressure. In the current investigation, the composite is comprised of Methyl methacrylate (MMA)-based infusible lamination resin combined with benzoyl peroxide initiator, which polymerizes into a Polymethyl methacrylate (PMMA) matrix. For the reinforcement, unidirectional 220 gr/m2 glass filament fabric was used. Delamination damage is artificially induced during the fabrication of laminate plates. The distributed delamination region before and after thermally activated healing was determined by using non-destructive testing with active thermography. An experimental approach is employed to characterize the thermal healing effect on mechanical properties. Experimentally determined technological parameters for thermal healing have been successfully applied to repair delamination defects on composite plates. Based on the compression-after-impact (CAI) test methodology, the intact, damaged, and healed composite laminates were loaded cyclically to evaluate the healing effect on stiffness and strength. During the CAI test, the 3D digital image correlation (DIC) technique was used to measure the displacement and deformation fields. Experimental results reveal the difference between the behavior of healed and damaged specimens. Additionally, the numerical models of intact, damaged, and healed composite laminates were developed using the finite element code LS-Dyna. Numerical models with calibrated material properties and tie-break contact constants provide good correlation with experimental results and allow for the prediction of the mechanical behavior of intact, damaged, and healed laminated plates. The comparison analysis based on CAI test results and modal characteristics obtained by the 3D Laser Doppler Vibrometer (Polytec GmbH, Karlsbad, Germany) proved that thermal healing partially restores the mechanical properties of damaged laminate plates. In contrast, active thermography does not necessarily indicate a healing effect.

6.
Materials (Basel) ; 16(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37570115

RESUMEN

This research utilizes Ultrasonic Guided Waves (UGW) to inspect corrosion-type defects in steel pipe walls, providing a solution for hard-to-reach areas typically inaccessible by traditional non-destructive testing (NDT) methods. Fundamental helical UGW modes are used, allowing the detection of defects anywhere on the pipe's circumference using a limited number of transducers and measurements on the upper side of the pipe. Finite element (FE) modeling and experiments investigated generating and receiving UGW helical waves and their propagation through varying corrosion-type defects. Defect detection is based on phase delay differences in the helical wave's signal amplitude peaks between defective and defect-free regions. Phase delay variations were noted for the different depths and spatial dimensions of the defects. These results highlight the phase delay method's potential for NDT pipeline inspection.

7.
Sensors (Basel) ; 23(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37514800

RESUMEN

Pipeline structures are susceptible to corrosion, leading to significant safety, environmental, and economic implications. Existing long range guided wave inspection systems often fail to detect footprints of the concentrated defects, which can lead to leakage. One way to tackle this issue is the utilization of circumferential guided waves that inspect the pipe's cross section. However, achieving the necessary detection resolution typically necessitates the use of high-order modes hindering the inspection data interpretation. This study presents the implementation of an ultrasonic technique capable of detecting and classifying wall thinning and concentrated defects using high-order guided wave modes. The technique is based on a proposed phase velocity mapping approach, which generates a set of isolated wave modes within a specified phase velocity range. By referencing phase velocity maps obtained from defect-free stages of the pipe, it becomes possible to observe changes resulting from the presence of defects and assign those changes to the specific type of damage using artificial neural networks (ANN). The paper outlines the fundamental principles of the proposed phase velocity mapping technique and the ANN models employed for classification tasks that use synthetic data as an input. The presented results are meticulously verified using samples with artificial defects and appropriate numerical models. Through numerical modeling, experimental verification, and analysis using ANN, the proposed method demonstrates promising outcomes in defect detection and classification, providing a more comprehensive assessment of wall thinning and concentrated defects. The model achieved an average prediction accuracy of 92% for localized defects, 99% for defect-free cases, and 98% for uniform defects.

8.
Pharmaceutics ; 15(5)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37242705

RESUMEN

Microbubble (MB)- and ultrasound (US)-facilitated intracellular Ca2+ delivery, known as sonoporation (SP), is a promising anticancer treatment modality, since it allows a spatio-temporally controllable and side-effect-free alternative to conventional chemotherapy. The current study provides extensive evidence that a 5 mM concentration of Ca2+ in combination with US alone or US and Sonovue MBs can be an alternative to the conventional 20 nM concentration of the anticancer drug bleomycin (BLM). Ca2+ application together with SP induces a similar level of death in Chinese hamster ovary cells to the combination of BLM and SP but does not cause systemic toxicity, as is inherent to conventional anticancer drugs. In addition, Ca2+ delivery via SP alters three vital characteristics essential for viable cells: membrane permeability, metabolic activity and proliferation ability. Most importantly, Ca2+ delivery via SP elicits sudden cell death-occurring within 15 min-which remains similar during 24-72 h and 6 d periods. The extensive study of US waves side-scattered by MBs led to the quantification of the cavitation dose (CD) separately for subharmonics, ultraharmonics, harmonics and broadband noise (up to 4 MHz). The CD was suitable for the prognostication of the cytotoxic efficiency of both anticancer agents, Ca2+ and BLM, as was indicated by an overall high (R2 ≥ 0.8) correlation (22 pairs in total). These extensive analytical data imply that a broad range of frequencies are applicable for the feedback-loop control of the process of US-mediated Ca2+ or BLM delivery, successively leading to the eventual standardization of the protocols for the sonotransfer of anticancer agents as well as the establishment of a universal cavitation dosimetry model.

9.
Materials (Basel) ; 17(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38204016

RESUMEN

High-density polyethylene (HDPE) pipes are becoming increasingly popular, being used in various fields, such as construction, marine, petroleum, water transfer, process water, methane gas collection, oil and gas gathering, gas distribution systems, mining, acid and wet gas lines, offshore oil and gas and in nuclear power plants. Higher-order guided Lamb wave (UGW) modes can be used to detect various defects in complex structures. We will apply this methodology to one of the types of plastic-the structure of high-density polyethylene (HDPE). However, the excitation of UGW modes faces numerous challenges, especially when there is a need to identify which mode is excited. It is essential to note that, in the higher frequency range, multiple different higher-order modes can usually be excited. This can make it difficult to determine which modes have actually been excited. The objective of this research was to successfully excite and receive various higher-order UGW modes in high-density polyethylene structures using both ultrasonic single-element transducers and a phased array. Theoretical calculations were performed using a variety of methods: semi-analytical finite element (SAFE) method, 2D spatial-temporal spectrum analysis and finite element modeling (FEM). The results obtained from both measurements and simulations clearly demonstrate the possibility of efficiently exciting and receiving different Lamb wave modes possessing different phase velocities.

10.
Sensors (Basel) ; 22(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36146100

RESUMEN

The 2D-FFT is described as a traditional method for signal processing and analysis. Due to the possibility to determine the time and frequency (t,f) domains, such a method has a wide application in various industrial fields. Using that method, the obtained results are presented in images only; thus, for the extraction of quantitative values of phase velocities, additional algorithms should be used. In this work, the 2D-FFT method is presented, which is based on peak detection of the spectrum magnitude at particular frequencies for obtaining the quantitative expressions. The radiofrequency signals of ULWs (ultrasonic Lamb waves) were used for the accuracy evaluation of the method. An uncertainty evaluation was conducted to guarantee the metrological traceability of measurement results and ensure that they are accurate and reliable. Mathematical and experimental verifications were conducted by using signals of Lamb waves propagating in the aluminum plate. The obtained mean relative error of 0.12% for the A0 mode (160 kHz) and 0.05% for the S0 mode (700 kHz) during the mathematical verification indicated that the proposed method is particularly suitable for evaluating the phase-velocity dispersion in clearly expressed dispersion zones. The uncertainty analysis showed that the plate thickness, the mathematical modeling, and the step of the scanner have a significant impact on the estimated uncertainty of the phase velocity for the A0 mode. Those components of uncertainty prevail and make about ~92% of the total standard uncertainty in a clearly expressed dispersion range. The S0 mode analysis in the non-dispersion zone indicates that the repeatability of velocity variations, fluctuations of the frequency of Lamb waves, and the scanning step of the scanner influence significantly the combined uncertainty and represent 98% of the total uncertainty.

11.
Materials (Basel) ; 14(22)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34832389

RESUMEN

The possibilities of an effective method of two adjacent signals are investigated for the evaluation of Lamb waves phase velocity dispersion in objects of different types, namely polyvinyl chloride (PVC) film and wind turbine blade (WTB). A new algorithm based on peaks of spectrum magnitude is presented and used for the comparison of the results. To use the presented method, the wavelength-dependent parameter is proposed to determine the optimal distance range, which is necessary in selecting two signals for analysis. It is determined that, in the range of 0.17-0.5 wavelength where δcph is not higher than 5%, it is appropriate to use in the case of an A0 mode in PVC film sample. The smallest error of 1.2%, in the distance greater than 1.5 wavelengths, is obtained in the case of the S0 mode. Using the method of two signals analysis for PVC sample, the phase velocity dispersion curve of the A0 mode is reconstructed using selected distances x1 = 70 mm and x2 = 70.5 mm between two spatial positions of a receiving transducer with a mean relative error δcph=2.8%, and for S0 mode, x1 = 61 mm and x2 = 79.7 mm with δcph=0.99%. In the case of the WTB sample, the range of 0.1-0.39 wavelength, where δcph is not higher than 3%, is determined as the optimal distance range between two adjacent signals. The phase velocity dispersion curve of the A0 mode is reconstructed in two frequency ranges: first, using selected distances x1 = 225 mm and x2 = 231 mm with mean relative error δcph=0.3%; and second, x1 = 225 mm and x2 = 237 mm with δcph=1.3%.

12.
Sensors (Basel) ; 21(14)2021 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-34300622

RESUMEN

The reliability of the wind turbine blade (WTB) evaluation using a new criterion is presented in the work. Variation of the ultrasonic guided waves (UGW) phase velocity is proposed to be used as a new criterion for defect detection. Based on an intermediate value between the maximum and minimum values, the calculation of the phase velocity threshold is used for defect detection, location and sizing. The operation of the proposed technique is verified using simulation and experimental studies. The artificially milled defect having a diameter of 81 mm on the segment of WTB is used for verification of the proposed technique. After the application of the proposed evaluation technique for analysis of the simulated B-scan image, the coordinates of defect edges have been estimated with relative errors of 3.7% and 3%, respectively. The size of the defect was estimated with a relative error of 2.7%. In the case of an experimentally measured B-scan image, the coordinates of defect edges have been estimated with relative errors of 12.5% and 3.9%, respectively. The size of the defect was estimated with a relative error of 10%. The comparative results obtained by modelling and experiment show the suitability of the proposed new criterion to be used for the defect detection tasks solving.

13.
Materials (Basel) ; 14(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668268

RESUMEN

This article compares different air-coupled ultrasonic testing methods to characterize impact-type defects in a pultruded quasi-isotropic glass fiber-reinforced plastic (GFRP) composite plate. Using the air-coupled transducers, comparisons among three methods were performed, namely, bulk-wave through transmission, single-side access using guided waves, and ultrasonic-guided wave tomography. The air coupled through transmission technique can determine the size and shape of impact-type defects with a higher resolution, but with the consequence of time consumption and, more importantly, the necessity of access to both sides of the sample. The guided wave technique on the other hand, allows a single-side inspection and is relatively fast. It can be used to determine the size of the defect using ultrasonic B-scan, but the exact shape of the defect will be compromised. Thus, in this article, to determine the shape of the defect, application of the parallel beam tomographic reconstruction technique using guided Lamb waves is demonstrated. Furthermore, a numerical finite element simulation was performed to study the effects of guided wave propagation in the composite sample and interaction with the internal defect. Lastly, the results from the experiments of different techniques were compared according to possibilities of defect sizing and determination of its shape.

14.
Sci Rep ; 10(1): 16161, 2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32999381

RESUMEN

The aim of our study was to evaluate the influence of low-intensity pulsed US on the delivery of doxorubicin (DOX) into MDA-MB-231 triple-negative breast cancer and A549 non-small cell lung cancer cell 2D and 3D cultures. US with pulse repetition frequency of 10 Hz and 1 MHz center frequency was generated with peak negative pressure of 0.5 MPa and 50% duty cycle. SonoVue microbubbles were used. Spheroids were formed using 3D Bioprinting method. DOX delivery in 2D and 3D cultures was assessed using fluorescence microscopy. US without the addition of microbubbles did not enhance the penetration of DOX into monolayer-cultured cells and tumor spheroids. In the presence of microbubbles US improved the delivery of DOX into the edge end middle zones of A549 and MDA-MB-231 spheroids. Application of low-intensity pulsed US in combination with microbubbles may be a promising approach to enhance the delivery of DOX into tumor spheroids.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Esferoides Celulares/efectos de los fármacos , Ondas Ultrasónicas , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/patología , Microburbujas , Neoplasias de la Mama Triple Negativas/patología
15.
Diagnostics (Basel) ; 10(9)2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-32858850

RESUMEN

Dermatoscopy, high-frequency ultrasonography (HFUS) and spectrophotometry are promising quantitative imaging techniques for the investigation and diagnostics of cutaneous melanocytic tumors. In this paper, we propose the hybrid technique and automatic prognostic models by combining the quantitative image parameters of ultrasonic B-scan images, dermatoscopic and spectrophotometric images (melanin, blood and collagen) to increase accuracy in the diagnostics of cutaneous melanoma. The extracted sets of various quantitative parameters and features of dermatoscopic, ultrasonic and spectrometric images were used to develop the four different classification models: logistic regression (LR), linear discriminant analysis (LDA), support vector machine (SVM) and Naive Bayes. The results were compared to the combination of only two techniques out of three. The reliable differentiation between melanocytic naevus and melanoma were achieved by the proposed technique. The accuracy of more than 90% was estimated in the case of LR, LDA and SVM by the proposed method.

16.
Sensors (Basel) ; 20(8)2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32316474

RESUMEN

Analytical modelling is an efficient approach to estimate the directivity of a transducer generating guided waves in the research field of ultrasonic non-destructive testing of the large and complex structures due to its short processing time as compared to the numerical modelling and experimental techniques. The wave patterns or the amplitude variations along the region of ultrasonic transducer itself depend on its behavior, excitation frequency, and the type of propagating wave mode. Depending on the wave-pattern of a propagating wave mode, the appropriate value of the amplitude correction factor must be multiplied to the amplitudes of the excitation signal for the accurate evaluation of directivity pattern of the ultrasonic transducers generating guided waves in analytical modelling. The objective of this work is to analyse the wave patterns under the region of macro-fiber composite (MFC) transducer to improve the accuracy of a previously developed analytical model for the prediction of directivity patterns. Firstly, the amplitude correction factor based on the wave patterns under the region of P1-type MFC (MFC-2814) transducer at two different frequencies (80 kHz, 3 periods and 220 kHz, 3 period) glued on 2 mm Al alloy plate has been estimated analytically in the case of an asymmetric (A0) guided Lamb wave. The validation of analytically estimated amplitude correction factor is performed by a proposed experimental method that allows analyzing the behaviour of MFC transducer under its region by gluing MFC on bottom surface and scanning the receiver on the top surface of the sample. Later on, the estimated amplitude correction factor is included in the previously developed 2D analytical model for the improvement in the directivity patterns of the A0 mode. The modified analytical model shows a significant improvement in the directivity pattern of the A0 wave mode in comparison to the results obtained by the previous model without considering the proper wave patterns. The results reveal that errors between the directivity estimated by the present modified 2D analytical model and experimental investigation are reduced by more than 58% in comparison to the previously developed analytical model.

17.
Materials (Basel) ; 13(7)2020 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-32260394

RESUMEN

Our previous studies have shown that the application of the proposed technique of a dual focused ultrasonic beam in two orthogonal cross-sections in passive (elevation) and active (azimuth) apertures of linear ultrasonic phased array transducer (ULPAT) enhances the 3D spatial resolution in the case of the inspection of conventional defects (flat bottom holes) or measurement of thickness of multi-layered metal composites. The objective of this work is to apply the proposed technique to enhance the spatial resolution of the ULPAT in the cases of detection and sizing demonstration of internal defects possessing spatially complex geometry, and during the inspection of defective multi-layered thin composite components (e.g., GLARE) of the aircraft fuselage. The specially prepared aluminium specimen possessing an internal defect of complicated geometry (crescent-shaped) was investigated. The simulation results and experiments demonstrate the resolution enhancement, higher amplitude of the reflections (e.g., 2.5 times or +8 dB) and spatial improvement in the defect detection even in the case of the non-perpendicular incidence of ultrasonic waves to the complex geometry surface of the internal defect. During the experiments, the multi-layered GFRP-metal based composite sample GLARE 3-3/2 was investigated in the case of the single-side access to the surface of the sample. The internal artificial delamination type defect of 25 mm was detected with a higher accuracy. Compared to the limitations of conventional ULPAT, the relative error (32%) (at the -6 dB level) of lateral defect dimensions estimation was completely reduced.

18.
Materials (Basel) ; 11(7)2018 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-29987253

RESUMEN

In this paper, the disbond-type defect presented on glass fiber reinforced plastic material is analyzed by refining the guided Lamb wave signals. A segment of wind turbine blade is considered as a test sample. The low-frequency ultrasonic measurement system is used for the non-destructive testing of the test sample using guided waves. The P-1 type macro-fiber composite transducer as a transmitter and contact-type piezoceramic transducer as a receiver are used for the testing of a sample. The disbond type defect having a diameter of 81 mm is detected from the experimental results. To improve the accuracy in locating and sizing the defects and estimation of the time of flight and phase velocity of ultrasonic guided waves in defective region, signal processing algorithm is developed by utilizing the promising properties of various ultrasonic signal processing techniques such as wavelet transform, amplitude detection, two-dimensional Fast-Fourier transform, Hilbert transform and variational mode decomposition. The discrete wavelet transform is used to denoise the guided wave signals and then, the size and location of defects are estimated by amplitude detection. The reflected wave signals from the opposite edge of the sample are removed by applying the two-dimensional Fast-Fourier transform to the experimental B-scan signal. Afterwards, variational mode decomposition and Hilbert transform are used for the phase velocity and time-delay estimation by comparing the instantaneous amplitudes of the defective and defect-free signal. The validation and the demonstration of reproducibility of the algorithm is performed by extracting the features of a 51 mm defect from another experimental B-scan.

19.
Microb Pathog ; 123: 144-148, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29981853

RESUMEN

High intensity ultrasound is becoming important and more widely used in the food industry for microorganisms decontamination. This sterilization technique has been evaluated to improve food safety and to replace common processing with chemical additive compounds. The efficiency of a horn-type power ultrasound treatment (300 W and 600 W, 28 kHz, 10-30 min) on Listeria monocytogenes, Bacillus cereus, Escherichia coli, Salmonella typhimurium bacteria suspensions and phytoviruses was examined in this study. The results of this study showed that ultrasonic treatment can be used to eliminate vegetative cells of gram-positive and gram-negative bacteria from 1.59 to 3.4 log in bacterial suspensions and some phytoviruses in fruits.


Asunto(s)
Bacterias/efectos de la radiación , Irradiación de Alimentos/métodos , Microbiología de Alimentos , Conservación de Alimentos/métodos , Ultrasonido/métodos , Virus/efectos de la radiación , Bacillus cereus/crecimiento & desarrollo , Bacillus cereus/efectos de la radiación , Bacterias/crecimiento & desarrollo , Recuento de Colonia Microbiana , Escherichia coli/crecimiento & desarrollo , Escherichia coli/efectos de la radiación , Contaminación de Alimentos/prevención & control , Industria de Alimentos , Inocuidad de los Alimentos , Frutas/virología , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/efectos de la radiación , Viabilidad Microbiana/efectos de la radiación , Salmonella typhimurium/crecimiento & desarrollo , Salmonella typhimurium/efectos de la radiación , Ultrasonido/instrumentación , Virus/crecimiento & desarrollo
20.
Libyan J Med ; 13(1): 1479600, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29943665

RESUMEN

Ultrasonic and digital dermatoscopy diagnostic methods are used in order to estimate the changes of structure, as well as to non-invasively measure the changes of parameters of lesions of human tissue. These days, it is very actual to perform the quantitative analysis of medical data, which allows to achieve the reliable early-stage diagnosis of lesions and help to save more lives. The proposed automatic statistical post-processing method based on integration of ultrasonic and digital dermatoscopy measurements is intended to estimate the parameters of malignant tumours, measure spatial dimensions (e.g. thickness) and shape, and perform faster diagnostics by increasing the accuracy of tumours differentiation. It leads to optimization of time-consuming analysis procedures of medical images and could be used as a reliable decision support tool in the field of dermatology.


Asunto(s)
Técnicas de Apoyo para la Decisión , Dermoscopía/estadística & datos numéricos , Procesamiento de Imagen Asistido por Computador/métodos , Melanoma/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Ultrasonografía/estadística & datos numéricos , Dermoscopía/métodos , Detección Precoz del Cáncer/métodos , Humanos , Modelos Logísticos , Melanocitos/patología , Melanoma/patología , Curva ROC , Neoplasias Cutáneas/patología , Ultrasonografía/métodos
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