Learn More
Measurements of hepatic iron concentration (HIC) are important predictors of transfusional iron burden and long-term outcome in patients with transfusion-dependent anemias. The goal of this work was to develop a readily available, noninvasive method for clinical HIC measurement. The relaxation rates R2 (1/T2) and R2* (1/T2*) measured by magnetic resonance(More)
—Rotary traveling-wave oscillators (RTWOs) represent a new transmission-line approach to gigahertz-rate clock generation. Using the inherently stable LC characteristics of on-chip VLSI interconnect, the clock distribution network becomes a low-impedance distributed oscillator. The RTWO operates by creating a rotating traveling wave within a closed-loop(More)
This paper considers an approach to nonlinear model-order reduction for RF/microwave integrated circuits (ICs) from the perspective of "black-box" behavioral modeling. We present a systematic methodology for creating behavioral models using techniques developed from concepts in system identification, nonlinear dynamics, computational geometry, and(More)
PURPOSE To determine normative R2* values in the liver and heart at 3T, and establish the relationship between R2* at 3T and 1.5T over a range of tissue iron concentrations. MATERIALS AND METHODS A total of 20 healthy control subjects and 14 transfusion-dependent patients were scanned at 1.5T and 3T. At each field strength R2* imaging was performed in the(More)
BACKGROUND Transfusional therapy for thalassemia major and sickle cell disease can lead to iron deposition and damage to the heart, liver, and endocrine organs. Iron causes the MRI parameters T1, T2, and T2* to shorten in these organs, which creates a potential mechanism for iron quantification. However, because of the danger and variability of cardiac(More)
We present an optimal experiment design methodology and a superior and fully automated model generation procedure for identifying a class of broad-band multiharmonic behavioral models in the frequency domain. The approach reduces the number of nonlinear measurements needed, minimizes the time to generate the data from simulations, reduces the time to(More)
PURPOSE To study the pattern, etiology, and significance of renal iron accumulation in chronically transfused sickle cell disease (SCD) and thalassemia major (TM) patients using magnetic resonance imaging (MRI). MATERIALS AND METHODS Magnetic resonance imaging (MRI) was performed in 75 SCD patients, 73 TM patients, and 16 healthy controls. Multiecho(More)
Two sets of molecular descriptors, the five experimental Abraham, and the five COSMOments of Klamt's COSMO-RS, have been compared for a data set of 470 compounds. Both sets are considered as almost complete sets of LFER. The two sets of descriptors are shown to exhibit a large overlap as far as their chemical content. The chemical information however is(More)
A new nonlinear charge-conservative scalable dynamic electro-thermal compact model for laterally defused MOS (LDMOS) RF power transistors is described in this paper. The transistor is characterized using pulsed <i>I-V</i> and S-parameter measurements, to ensure isothermal conditions. A new extrinsic network and extrinsic parameter-extraction methodology is(More)
To meet the needs of term and preterm neonates undergoing magnetic resonance (MR) imaging, an MR-compatible incubator with air, temperature, and humidity regulators and integrated radiofrequency coils was evaluated. Nine brain, two cardiac, and two pelvic examinations were performed by using a 1.5-T clinical MR imaging unit. The axillary temperature of the(More)