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作者： Cortela, G.A. Von Kruger, M.A. MacHado, C.B. Negreira, C.A. Pereira, W.C.A. Laboratorio de Acústica Ultrasónica UdelaR Montevideo Uruguay Biomedical Engineering Program COPPE/UFRJ Rio de Janeiro RJ Brazil

ISBN: (纸本)9781612849164

Periodicity of structures can be investigated with backscattered ultrasound, usually by applying spectral methods and estimating the Mean Scatterer Spacing (MSS). Biological tissues, such as skeletal muscle, or liver or trabecular bone, can present periodic or quasi-periodic structures. In this work it is studied the behavior of MSS with temperature and frequency for in vitro samples of bovine muscular tissues. MSS was obtained in the range of 37C to 43C, and between 1 MHz to 10.0 MHz Results show that, for the studied sample, MSS decreased with temperature for the muscle. It seems to be in agreement with the expected physiologic behavior of muscular fibers. Further complementary experiments are being envisaged. © 2011 IEEE.

关键词： Ultrasonics

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Evaluating periodicity of trabecular bone phantoms using ultrasound signals

Evaluating periodicity of trabecular bone phantoms using ult...

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Pan American Health Care Exchanges, PAHCE 2011 - Conference, Workshops, and Exhibits. Cooperation / Linkages: An Independent Forum for Patient Care and Technology Support

作者： Rosa, P.T.C.R. Matusin, D.P. Pereira, A.J.F. MacHado, C.B. Pereira, W.C.A. Biomedical Engineering Program/COPPE Federal University of Rio de Janeiro RJ Brazil Laboratoire d'Imagerie Paramétrique Université Paris VI France

ISBN: (纸本)9781612849164

The aim of this work was to characterize the periodicity of a commercial available trabecular bone phantom with ultrasound (US) backscattered signals. Three US frequencies were applied (1.0, 2.25 and 5.0 MHz), and spectral analysis methods were used to estimate the mean scatterer spacing (MSS) of 100 signals/sample from five different samples. The results showed that it is possible to estimate the medium periodicity (trabecular spacings varying from 1.5 to 2.5 mm), and at higher frequencies the average MSS decreased, which is expected because of a higher spatial resolution (identification of the trabecular thickness periodicity). MSS values are in agreement with intertrabecular distances declared by the product supplier. © 2011 IEEE.

关键词： Ultrasonics

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The effect of bone fracture unevenness on ultrasound axial transmission measurements: A pilot 2D simulation study

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AIP Conference Proceedings 2012年第1期1433卷 219-222页

作者： Christiano B. Machado Wagner C. A. Pereira Frédéric Padilla Pascal Laugier Estácio de Sá University - Jardim Sans Souci s/n Braunes Nova Friburgo - RJ Brazil Biomedical Engineering Program COPPE/Federal University of Rio de Janeiro - Technology Center Block H Ilha do Fundão Rio de Janeiro Brazil Department of Radiology University of Michigan Medical Center Ann Harbor MI USA Laboratoire d'Imagerie Paramétrique UPMC Univ Paris 6 CNRS - 15 rue de l'École de Médécine Paris France

Ultrasound axial transmission (UAT) has been proposed to the diagnosis and follow-up of fracture healing. Some researchers have already pointed out the influence of fracture length, geometry and callus composition on the ultrasound time-of-flight and attenuation, with experimental and simulation studies. The aim of this work was to develop a pilot study on the effect of bone fracture unevenness on UAT measurements. Two-dimensional (2D) numerical simulations of ultrasound wave propagation were run using a custom-made finite-difference time domain code (SimSonic2D). Numerical models were composed of two 4-mm thick bone plates, with fracture lengths varying from 0 to 4 mm. For each case, an upward (UWun) and downward (DWun) unevenness of 0.5, 1.0 and 1.5 mm was implemented in the second plate. The 1-MHz emitter and receptor transducers were placed at 40 mm from each other, 20 mm apart from the center fracture. Two configurations were considered: 1.5 mm above the plates (for the 0-mm unevenness case) and transducers in contact with bone plate. For each situation, the time-of-flight of the first arriving signal (TOFFAS) and the FAS energy amplitude loss measured by the sound pressure level (SPLFAS) were computed. Results showed that there was a linear increase in TOFFAS with increasing fracture length, and a decrease of SPLFAS with the presence of a discontinuity. TOFFAS values were decreased with UWun (−0.87 μs for UWun = 1.5 mm), and increased with DWun (+0.99 μs for DWun = 1.5 mm). The SPLFAS increased with both UWun (+3.54 dB for UWun = 1.5 mm) and DWun (+8.15 dB for DWun = 1.5 mm). Both parameters showed the same variability. When transducers were put in contact with bone surface, fracture unevenness had no influence on TOF and SPL estimates. Previous works have already demonstrated that a fracture of 3 mm can increase TOFFAS in an order of 1 μs. Considering these preliminary results, it can be concluded that, although the variable fracture unevenness (until 1.5 mm)

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Reports on Homeopathic therapy efficacy: A survey of two Brazilian newspapers

Reports on Homeopathic therapy efficacy: A survey of two Bra...

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Pan American Health Care Exchanges, PAHCE

作者： R. M. V. R. Almeida Biomedical Engineering Program COPPE/UFRJ Rio de Janeiro Brazil

The objective of this work was to identify the existence of biases on the reporting of Homeopathy efficacy in Brazilian newspapers. To this end, the online archives of two large newspapers - one in Rio de Janeiro city and one in São Paulo city - were searched for all news or reports concerning Homeopathy in the period January 2009-December 2010. The identified items were then classified as “favorable”, “unfavorable” or “neutral” in what concerns the efficacy of Homeopathic therapy. Paid advertisements and “passing” references were excluded. Thirty-one items were identified, and the results indicated an overall preponderance of “favorable”, as compared to “unfavorable“, reports (14 favorable, 7 unfavorable). In conclusion, newspaper reporting of homeopathic efficacy is not compatible with the most update scientific evidence on the topic.

关键词： Animals Diseases Pediatrics Stress Cities and towns

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Analysis of different techniques for measuring the attenuation coefficient in ultrasonic phantom

Analysis of different techniques for measuring the attenuati...

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Pan American Health Care Exchanges, PAHCE 2011 - Conference, Workshops, and Exhibits. Cooperation / Linkages: An Independent Forum for Patient Care and Technology Support

作者： Maggi, L.E. Costa, J.F.S. Cortela, G.A. Pereira, W.C.A. Von Kruger, M.A. State University of Goiás Goiânia GO Brazil Biomedical Engineering Program COPPE/UFRJ Rio de Janeiro RJ Brazil Ultrasonic Acoustics Laboratory UDELAR Montevideo Uruguay

ISBN: (纸本)9781612849164

This work describes some techniques for estimating the attenuation coefficient of longitudinal wave in a phantom made with RTV615 (GE) and silicone. The AWAY method presented results with lower standard deviation when RMS or FFT was applied to analyze the ultrasonic signal. Furthermore, it was observed that the use of APPARENT AWAY method with the FFT has sensitivity to number of cycles of the burst used, because the increased number of cycles considerably reduced the standard deviation of the results. However, if the number of cycles is greater than 10, the application of FFT and RMS methods gave similar results and should provide the same standard deviation. © 2011 IEEE.

关键词： Phantoms

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The effect of cortical bone mineralization in ultrasound axial transmission: On the possibility of fracture healing monitoring

The effect of cortical bone mineralization in ultrasound axi...

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Pan American Health Care Exchanges, PAHCE 2011 - Conference, Workshops, and Exhibits. Cooperation / Linkages: An Independent Forum for Patient Care and Technology Support

作者： MacHado, C.B. Pereira, W.C.A. Talmant, M. Padilla, F. Laugier, P. Laboratoire d'Imagerie Paramétrique Université Paris 6 France Biomedical Engineering Program COPPE/UFRJ Rio de Janeiro Brazil Department of Radiology University of Michigan Medical Center MI United States

ISBN: (纸本)9781612849164

The present work aims at studying the effect of cortical bone mineralization on ultrasound axial transmission (UAT) measurements, using experiments and numerical simulations. To this end, a reverse fracture healing approach is proposed, using an in vitro bovine femur sample. A demineralization protocol was applied, and the time-of-flight of the wave propagating in axial transmission measured. Numerical simulations of the experimental situation were also implemented. Mineralization degree may influence ultrasound measurements, and it may be a promising tool for fracture healing assessment. © 2011 IEEE.

关键词： Bone

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Evaluation of heating patterns generated by therapeutic ultrasound insonation in muscle phantoms

Evaluation of heating patterns generated by therapeutic ultr...

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Pan American Health Care Exchanges, PAHCE

作者： R. L. Q. Basto N. S. Amorim E. R. Monteiro J. N. N. Quaresma R. M. Cotta M. A. von Krüger W. C. A. Pereira POLI & COPPE LTTC-Laboratory of Transmission and Technology of Heat Mechanical Engineering Program UFRJ Rio de Janeiro Brazil COPPE Laboratory of Ultrasound Biomedical Engineering Program UFRJ Rio de Janeiro Brazil

The present work aims at studying the effect of heating patterns generated by therapeutic ultrasound (US) insonation on tissue mimicking device called Phantom. With this purpose, it was constructed a cylindrical calorimeter (80 mm height and 42 mm diameter) which was filled with muscle mimic phantom, for acquisition of temperature an array of thermocouples was placed at 2 and 6 cm depth. Ultrasound physiotherapy equipment was used at two therapeutic frequency (1 and 3 MHz), three intensities, and continuous irradiation mode and applied for 300s static mode. The experimental temperatures elevation profiles in Phantom were compared to a 2D bio-heat equation model, permitting a critical evaluation of such experimental data. The acoustic heating model was based on the US absorption equation, assuming linear propagation and neglecting stationary wave and multiplies reverberation effects. The comparison between experimental and mathematical simulation for the central thermocouple showed that, for far field the correlation between the experimental and simulated values are higher than for the near field.

关键词： Ultrasonic imaging Phantoms Biological system modeling Mathematical model Temperature distribution Temperature measurement Heating

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Evaluating pharmaceutical assistance activities in Brazilian hospitals

Evaluating pharmaceutical assistance activities in Brazilian...

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Pan American Health Care Exchanges, PAHCE

作者： A. Nascimento S. R. Castilho R. M. V. R. Almeida A. F. C. Infantosi Biomedical Engineering Program /COPPE UFRJ Rio de Janeiro Brazil Pharmacy Faculty UFF Niteroi Brazil

This work aims at identifying and evaluating the associations between the pharmaceutical assistance activities in hospital pharmacies services (HPS). The Multiple Correspondence Analysis (MCA) was applied to a sample of 238 hospitals and 30 variables from the survey Diagnosis of Hospital Pharmacy in Brazil. The first dimension of the MCA explained 90.6% of the data variability and allowed discriminate the HPS according to the presence or not of activities. It is noticeable an association between the presence of activities and better categories with large hospitals.

关键词： Hospitals Drugs Conferences Logistics IEEE catalog Couplings

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Independent component analysis for reducing electrocardiographic interference in the multichannel electromyogram

Independent component analysis for reducing electrocardiogra...

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作者： Júnior, J.D.Costa De Seixas, J.M. Nadal, J. De Sá, A.M.F.L.Miranda Biomedical Engineering Program Federal University of Rio de Janeiro COPPE/UFRJ P.O. Box 68512 ZIP 21941-972 Rio de Janeiro Brazil Signal Processing Laboratory Federal University of Rio de Janeiro Rio de Janeiro Brazil

The aim of this work was to separate ECG artifacts from surface electromyogram (EMG) signals collected from erector spinae muscles with the blind source separation technique based on independent component analysis (ICA) and to investigate the separation at different interference levels. Using three EMG signals collected above erector spinal muscles from 5 subjects, the proposed method succeeds in separating the sources in both real and simulated signals. However, the ICA is not able to separate the signals when the signal-to-interference ratio is greater than 20 dB. © 2011 Springer-Verlag Berlin Heidelberg.

关键词： Electromyography

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Effects of Intense Physical Activity with Free Water Replacement on Bioimpedance Parameters and Body Fluid Estimates

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Journal of Physics: Conference Series 2012年第1期407卷

作者： E B Neves L Ulbricht E Krueger E F R Romaneli M N Souza Biomedical Engineering Master Program/PPGEB Federal Technological University of Paraná Av. Sete de Setembro 3165 80230-901 Curitiba/PR Brazil Rehabilitation Engineering Laboratory Federal Technological University of Paraná Av. Sete de Setembro 3165 80230-901 Brazil Automation and Control Engineering Academic Department of Electrotechnics Federal Technological University of Paraná Av. Sete de Setembro 3165 80230-901 Brazil Biomedical Engineering Program – COPPE/UFRJ Centro de Tecnologia Bloco H sala 327 21949-900 Brazil

Authors have emphasized the need for previous care in order to perform reliable bioimpedance acquisition. Despite of this need some authors have reported that intense physical training has little effect on Bioimpedance Analysis (BIA), while other ones have observed significant effects on bioimpedance parameters in the same condition, leading to body composition estimates considered incompatible with human physiology. The aim of this work was to quantify the changes in bioimpedance parameters, as well as in body fluids estimates by BIA, after four hours of intense physical activity with free water replacement in young males. Xitron Hydra 4200 equipment was used to acquire bioimpedance data before and immediately after the physical training. After data acquisition body fluids were estimates from bioimpedance parameters. Height and weight of all subjects were also acquired to the nearest 0.1 cm and 0.1 kg, respectively. Results point that among the bioimpedance parameter, extracellular resistance presented the most coherent behavior, leading to reliable estimates of the extracellular fluid and part of the total body water. Results also show decreases in height and weight of the participants, which were associated to the decrease in body hydration and in intervertebral discs.

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