Optical Flow-Based Tracking of Needles and Needle-Tip Localization Using Circular Hough Transform in Ultrasound Images.

Image-guided interventions have become the standard of care for needle-based procedures. The success of the image-guided procedures depends on the ability to precisely locate and track the needle. This work is primarily focused on 2D ultrasound-based tracking of a hollow needle (cannula) that is composed of straight segments connected by shape memory alloy actuators.

Pulse width modulation-based temperature tracking for feedback control of a shape memory alloy actuator.

This work presents a temperature-feedback approach to control the radius of curvature of an arc-shaped shape memory alloy (SMA) wire. The nonlinear properties of the SMA such as phase transformation and its dependence on temperature and stress make SMA actuators difficult to control. Tracking a desired trajectory is more challenging than controlling just the position of the SMA actuator since the desired path is continuously changing.

Towards A Discretely Actuated Steerable Cannula for Diagnostic and Therapeutic Procedures.

We have designed, developed, and evaluated the performance of a multi-degree-of-freedom discretely actuated steerable cannula with shape memory alloy (SMA)actuators. This will enable us to deliver diagnostic as well as therapeutic devices to the target location through the hollow inner core of the cannula. We propose to use SMAs to generate bending forces due to its small size and high power density.

Association of serum levels of IGF-I and IGFBP-1 with renal function in patients with type 2 diabetes mellitus.

Objective: Our aim was to determine whether serum Insulin-like growth factor-I (IGF-I) and Insulin-like growth factor binding protein-1 (IGFBP-1) levels were different between type 2 diabetic patients and non-diabetic control group. We also aimed to establish any relationship that might exist between the serum IGF-I and IGFBP-1 levels with the urinary albumin excretion (UAE), creatinine clearance and urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion (as a marker of renal tubular dysfunction) and other parameters (such as age, duration of diabetes, treatment, etc.) in patients with type 2 diabetes mellitus (DM).

Are growth factors and leptin involved in the pathogenesis of premature adrenarche in girls?

A transient increase in height and bone age as well as hyperinsulinism is seen in patients with premature adrenarche (PA). In addition, the weights of these patients are more than those of healthy peers. The aim of this study was to evaluate the role of leptin, IGF-I and IGFBPs in hyperandrogenemia and increased body weight observed in girls with PA.