Review of the safety, efficacy and patient acceptability of the levonorgestrel-releasing intrauterine system

The levonorgestrel-containing intrauterine system is an extremely effective, reversible and safe form of long-term yet reversible birth control. In view of its efficacy, it is a safer alternative to permanent contraceptive methods such as sterilization. It is especially useful in situations where use of estrogen-containing contraceptives is contraindicated. While menstrual disturbances are a common side effect, proper counseling improves compliance. In addition to its contraceptive effect, the levonorgestrel intrauterine system offers potential therapeutic benefits in other clinical contexts, including menorrhagia, symptomatic fibroids, endometriosis, and endometrial protection

Highly sensitive and high throughput magnetic resonance thermometry using superparamagnetic nanoparticles

Magnetic resonance imaging (MRI) enables non-invasive 3D thermometry during thermal ablation of cancerous tumors. While T1 or T2 contrast MRI are relatively insensitive to temperature, techniques with greater temperature sensitivity such as chemical shift or diffusion imaging suffer from motional artifacts and long scan times. We describe an approach for highly sensitive and high throughput MR thermometry that is not susceptible to motional artifacts. We use superparamagnetic iron oxide nanoparticles (SPIONs) to spoil T2 of water protons. Motional narrowing results in proportionality between T2 and the diffusion constant, dependent only on the temperature in a specific environment. Our results show, for pure water, the nuclear magnetic resonance (NMR) linewidth and T2 follow the same temperature dependence as the self-diffusion constant of water. Thus, T2 mapping is a diffusion mapping in the presence of SPIONs, and T2 is a thermometer. For pure water, a T2 mapping of a 64 x 64 image (voxel size = 0.5 mm x 0.5 mm x 3 mm) in a 9.4 T MRI scanner resulted in a temperature resolution of 0.5 K for a scan time of 2 minutes. This indicates a highly sensitive and high throughput MR thermometry technique potentially useful for monitoring of biological tissues during thermal therapies or for diagnosis

Deconfinement and Hadron Properties at Extremes of Temperature and Density

After introducing essential, qualitative concepts and results, we discuss the application of Dyson-Schwinger equations to QCD at finite T and mu. We summarise the calculation of the critical exponents of two-light-flavour QCD using the chiral and thermal susceptibilities; and an algebraic model that elucidates the origin of an anticorrelation between the mu- and T-dependence of a range of meson properties. That model also provides an algebraic understanding of why the finite-T behaviour of bulk thermodynamic properties is mirrored in their mu-dependence, and why meson masses decrease with mu even though f_pi and - increase. The possibility of diquark condensation is canvassed. Its realisation is uncertain because it is contingent upon an assumption about the quark-quark scattering kernel that is demonstrably false in some applications; e.g., it predicts the existence of coloured diquarks in the strong interaction spectrum, which are not observed.Comment: Summary of presentations at the Workshop on QCD at Finite Baryon Density, Bielefeld, Germany, 27-30/April/1998, 13 pages, 9 figures, espcrc1.sty, epsfig.sty. Correcting typsetting problem