In magnetic nanoparticle imaging, magnetic nanoparticles are coated and functionalized to bind to specific targets. After measuring their magnetic relaxation or remanence, their distribution can be determined by means of inverse methods. The reconstruction algorithm presented in this paper includes first a dipole fit using a Levenberg-Marquardt optimizer to determine the reconstruction plane. Secondly, a minimum norm estimate is obtained on a regular grid placed in that plane. Computer simulations involving different parameter sets and conditions show that the used approach allows for the reconstruction of distributed sources, although the reconstructed shapes are distorted by blurring effects. The reconstruction quality depends on the signal-to-noise ratio of the measurements and decreases with larger sensor-source distances and higher grid spacings. In phantom measurements, the magnetic remanence of nanoparticle columns with clinical relevant sizes is determined with two common measurement systems. The reconstructions from these measurements indicate that the approach is applicable for clinical measurements. Our results provide parameter sets for successful application of minimum norm approaches to Magnetic Nanoparticle Imaging.

In our randomized controlled study, we found no difference in the incidence of EA or ED between sevoflurane and isoflurane. Therefore, the decision to use one or the other should not be based upon the incidence of EA or ED.

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A bstractAmorphous silicon ®lms have been deposited on glass by subatmosphericpressure chemical vapour deposition and then crystallized by solid-phase crystallization. The structural and electrical properties of these polycrystalline silicon ®lms are presented in this work. Good crystalline quality at a deposition pressure of about 400 mbar has been achieved as well as values of the mobility± lifetime product above 10 ¡ 5 cm 2 V ¡ 1 and an ambipolar di usion length near 200 nm. Depending upon the deposition temperature and pressure, growth rates of up to 20 mm h ¡ 1 can be obtained. In-situ doping with arsenic and boron has been studied using Hall e ect measurements. High mobilities around 45 cm 2 V ¡ 1 s ¡ 1 have been attained for highly n-type doped samples and mobilities in the range from 20 to 30 cm 2 V ¡ 1 s ¡ 1 for boron-doped samples.} 1. I ntroduction Polycrystalline silicon (polysilicon) has received attention as a material for thin-®lm transistors (Mimura et al. 1989), photovoltaic conversion of solar energy (Matsuyama et al. 1993), integrated circuit applications and microelectromechanica l systems (Tada et al. 2000). Although the technology of amorphous silicon (a-Si) is well established, the carrier mobilities are too small and instabilities arise with applied bias, an increase in temperature and on light exposure. Polysilicon does not have these limitations but grain boundaries degrade the electrical and optical properties.The possibility of depositing polysilicon material with device-quality electronic properties at moderate temperatures (below 600°C) compatible with the use of glass substrates is interesting for industrial applications. It is known that silicon ®lms deposited by thermal chemical vapour deposition (CVD) in an amorphous state