Several major lung pathologies are characterized by early modifications of the extracellular matrix (ECM) fibrillar collagen and elastin network. We report here the development of a nonlinear fiber-optic spectrometer, compatible with an endoscopic use, primarily intended for the recording of second-harmonic generation (SHG) signal of collagen and two-photon excited fluorescence (2PEF) of both c...

this paper presents a mathematical model for the vibration analysis of a three-component piezoelectric force sensor. the cubic theory of weakly nonlinear electroelasticity is applied to the model for describing the electromechanical coupling effect in the piezoelectric sensing elements which operate in thickness-shear and thickness-stretch vibration modes. hamilton's principle is used to d...

It is well accepted that soft tissue deformation a combination of linear and nonlinear response. During small displacements, tissues deform linearly while during large show deformation. This paper presents new approach for modelling deformation, from the standpoint Mass Spring Method (MSM). The proposed MSM model developed using conical spring methodology which allow to have different stiffness...

Fluorescence diffuse imaging (FDI) suffers from limited spatial resolution. In this Letter, we report a scanning imaging approach to increase the resolution of FDI using nonlinear fluorophores. The resolution of a linear fluorophore was compared with nonlinear upconverting nanoparticles (NaYF(4):Yb(3+)/Tm(3+)) in a tissue phantom. A resolution improvement of a factor of 1.3 was found experiment...

The nonlinear mechanical behavior of tissues that undergo large deformations, e.g. the breast, is characterized by hyperelastic parameters. These parameters take into account both types of nonlinearities: tissue intrinsic nonlinearity and geometric nonlinearity. Elastography technique capable of tissue hyperelastic parameter reconstruction has important clinical applications such as cancer diag...

in this paper, a complete model of an electro hydraulic driven dry clutch along with its performance evaluation has elucidated. through precision modeling, a complete nonlinear physical and full order sketch of clutch has drawn. ultimate nonlinearities existent in the system prohibits it from being controlled by conventional linear control algorithms and to compensate the behavior of the system...

Some acoustical nonlinear effects in biological media at medical ultrasonic frequencies and intensities were studied experimentally. The imaging method of acoustical nonlinearity parameter, as a basic parameter in nonlinear acoustics, was developed and investigated. Results indicate tidt the difference between normal and diseased tissues in nonlinearity parameter tomography is more sensitive th...

The noninvasiveness of nonlinear optical imaging techniques is quantified in terms of the number of free electron generated in the laser-tissue interaction region per photon emitted into the nonlinear optical signal. For a broad variety of biomarker dyes and bioactivity reporter proteins, this ratio is shown to approach a critical value of unity for field intensities above 1 TW/cm2. Closed-form...

severe hepatic failure accounts for many deaths and raises medical costs each year worldwide. currently, liver transplantation is the most common therapeutic option for patients with end-stage chronic liver disease. due to decrease in the number of organ donors, many in need of transplantation continue to remain on the waiting list. hepatic tissue engineering is a step toward alleviating the ne...

introduction: organ donation is one of the surviving procedures which can increase the life expectancy of end-stage patients. inappropriate beliefs and attitude of individuals to organ donation, their poor knowledge, and the socio-economic level are one of the most important barriers for organ donation. therefore, here knowledge and attitude levels among relatives of trauma patients regarding o...