| 1. |
- Castillo Leon, Jaime, et al.
(author)
-
Biosensors for life quality - Design, development and applications
- 2004
-
In: Sensors and Actuators B: Chemical. - : Elsevier BV. - 0925-4005. ; 102:2, s. 179-194
-
Journal article (peer-reviewed)abstract
- Biosensors, combining a selective biological recognition element and a sensitive transducer, are versatile analytical tools applied more and more in different fields, such as medicine, food quality and safety control, and environment pollution monitoring. They are expected to play an increasingly important role in the improvement of life quality. In this context, the present work covers recent approaches in design and development of biosensors applied for analysis of real samples of medical, environmental or industrial relevance. The described sensors meet the sensitivity, selectivity, and response time required by their applications. Moreover, they are designed to avoid contamination of the monitored systems with undesirable components and to minimise the damage of living organisms (when it comes to in vivo monitoring). (C) 2004 Elsevier B.V. All rights reserved.
|
|
| 2. |
- Pislaru, Cristina, et al.
(author)
-
Is there a change in myocardial nonlinearity during the cardiac cycle?
- 2001
-
In: Ultrasound in Medicine and Biology. - 0301-5629 .- 1879-291X. ; 27:3, s. 389-398
-
Journal article (peer-reviewed)abstract
- The distortion of a sound wave during propagation results in progressive transfer of the energy from fundamental to higher harmonics, and is dependent on the nonlinearity of the medium. We studied if relative changes in acoustical nonlinearity occur in healthy myocardium during the cardiac cycle. Radiofrequency data were acquired from transthoracic echocardiography (2.5 and 3.5 MHz), parasternal long axis view, from five dogs and nine healthy volunteers. Integrated backscatter was calculated after filtering for fundamental (FIB) and second harmonic frequencies (SHIB), from a region in the posterior myocardial wall. The results suggest that there is little difference between the SHIB and FIB, although there were large variations between individuals. The maximal changes in nonlinearity, as estimated by SHIB/FIB ratio, mostly occurred during systole. SHIB presented similar cyclic variation with FIB (p = NS). Further studies are necessary to separate the role of myocardial nonlinearity, attenuation, propagating distance, or acoustical properties of the blood. The results are important in further tissue characterization studies employing second harmonic data.
|
|
