Feasibility and accuracy of quantitative imaging on a 1.5 T MR-linear accelerator.

Purpose: Systems for magnetic resonance (MR-) guided radiotherapy enable daily MR imaging of cancer patients during treatment, which is of interest for treatment response monitoring and biomarker discovery using quantitative MRI (qMRI). Here, the performance of a 1.5 T MR-linac regarding qMRI was assessed on phantoms.

Performance of a fast and high-resolution multi-echo spin-echo sequence for prostate T mapping across multiple systems.

Purpose: To evaluate the performance of a multi-echo spin-echo sequence with k-t undersampling scheme (k-t T ) in prostate cancer.

Methods: Phantom experiments were performed at five systems to estimate the bias, short-term repeatability, and reproducibility across all systems expressed with the within-subject coefficient of variation (wCV). Monthly measurements were performed on two systems for long-term repeatability estimation.

Towards intrinsic R2* imaging in the prostate at 3 and 7tesla.

Purpose: Hypoxia is an important marker for resistance to therapy. In this study, we quantify the macroscopic effects of R2* mapping in prostate cancer patients incorporating susceptibility matching and field strengths effects.

Materials And Methods: 91 patients were scanned without endorectal coil (ERC) at 3T.

Significant tumor shift in patients treated with stereotactic radiosurgery for brain metastasis.

Introduction: Linac-based stereotactic radiosurgery (SRS) for brain metastases may be influenced by the time interval between treatment preparation and delivery, related to risk of anatomical changes. We studied tumor position shifts and its relations to peritumoral volume edema changes over time, as seen on MRI.

Methods: Twenty-six patients who underwent SRS for brain metastases in our institution were included.

Sisyphus cooling of electrically trapped polyatomic molecules.

Polar molecules have a rich internal structure and long-range dipole-dipole interactions, making them useful for quantum-controlled applications and fundamental investigations. Their potential fully unfolds at ultracold temperatures, where various effects are predicted in many-body physics, quantum information science, ultracold chemistry and physics beyond the standard model. Whereas a wide range of methods to produce cold molecular ensembles have been developed, the cooling of polyatomic molecules (that is, with three or more atoms) to ultracold temperatures has seemed intractable.

Continuous guided beams of slow and internally cold polar molecules.

We describe the combination of buffer-gas cooling with electrostatic velocity filtering to produce a high-flux continuous guided beam of internally cold and slow polar molecules. In a previous paper (L.D.

Magnetic trapping and Zeeman relaxation of NH (X3Sigma-).

NH radicals are magnetically trapped and their Zeeman relaxation and energy transport collision cross sections with helium are measured. Continuous buffer-gas loading of the trap is direct from a room-temperature molecular beam. The Zeeman relaxation (inelastic) cross section of magnetically trapped electronic, vibrational, and rotational ground state NH molecules in collisions with 3He is measured to be 3.