BACKGROUND The pluripotency and self renewing properties of human embryonic stem cells (hESC) make them a valuable tool in the fields of developmental biology, pharmacology and regenerative medicine. Therefore, there exists immense interest in devising strategies for hESC propagation and differentiation. Methods involving simulation of the native stem cell microenvironment, both chemical and ph...

A numerical method is presented for computing the time varying stresses in reciprocating compressor discharge tubes during starting. The tube is described using shell elements, and mounting springs are described using beam elements. Mass and stiffness matrices are assembled into a second order system of equations that is then solved in a time step fashion along with mechanism and induction moto...

Dynamic joint stiffness determines the relation between joint position and torque, and plays a vital role in the control of posture and movement. Dynamic joint stiffness can be quantified during quasi-stationary conditions using disturbance experiments, where small position perturbations are applied to the joint and the torque response is recorded. Dynamic joint stiffness is composed of intrins...

We present a composite material with embedded sensing and actuation that can perform permanent shape changes by temporarily varying its stiffness and applying an external moment. Varying stiffness is a complementary approach to actuator-chain based approaches that can be accomplished using a large variety of means ranging from heat, electric field or vacuum. A polycaprolactone (PCL) bar provide...

This paper focuses on the problem of finite-time boundedness and finite-time passivity of discrete-time T-S fuzzy neural networks with time-varying delays. A suitable Lyapunov--Krasovskii functional(LKF) is established to derive sufficient condition for finite-time passivity of discrete-time T-S fuzzy neural networks. The dynamical system is transformed into a T-S fuzzy model with uncertain par...

TEMPLETON, GORDON H., AND Louxs R. NARDTZZI. Elastic and viscous stifness of the canine left ventricle. J. Ap pl. Ph ysiol. 36 ( I ) : 123-I 27. 1974.-Elastic and viscous stiffness of canine left ventricles was measured continuously over the entire cardiac cycle. These mechanical properties were determined from the sinusoidally varying portion of the left ventricular pressure induced by an exte...